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<button class="button is-small is-link">Go</button> </div> </div> </form> </div> </div> <ol class="breathe-horizontal" start="1"> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2410.05156">arXiv:2410.05156</a> <span> [<a href="https://arxiv.org/pdf/2410.05156">pdf</a>, <a href="https://arxiv.org/format/2410.05156">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> </div> </div> <p class="title is-5 mathjax"> Brillouin-based storage of QPSK signals with fully tunable phase retrieval </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Saffer%2C+O">Olivia Saffer</a>, <a href="/search/physics?searchtype=author&query=Cabello%2C+J+H+M">Jes煤s Humberto Marines Cabello</a>, <a href="/search/physics?searchtype=author&query=Becker%2C+S">Steven Becker</a>, <a href="/search/physics?searchtype=author&query=Geilen%2C+A">Andreas Geilen</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2410.05156v1-abstract-short" style="display: inline;"> Photonic memory is an important building block to delay, route and buffer optical information, for instance in optical interconnects or for recurrent optical signal processing. Photonic-phononic memory based on stimulated Brillouin-Mandelstam scattering (SBS) has been demonstrated as a coherent optical storage approach with broad bandwidth, frequency selectivity and intrinsic nonreciprocity. Here,… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2410.05156v1-abstract-full').style.display = 'inline'; document.getElementById('2410.05156v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2410.05156v1-abstract-full" style="display: none;"> Photonic memory is an important building block to delay, route and buffer optical information, for instance in optical interconnects or for recurrent optical signal processing. Photonic-phononic memory based on stimulated Brillouin-Mandelstam scattering (SBS) has been demonstrated as a coherent optical storage approach with broad bandwidth, frequency selectivity and intrinsic nonreciprocity. Here, we experimentally demonstrated the storage of quadrature-phase encoded data at room temperature and at cryogenic temperatures. We store and retrieve the 2-bit states $\{00, 01, 10, 11\}$ encoded as optical pulses with the phases $\{0, 蟺/2 , 蟺, 3蟺/2\}$ - a quadrature phase shift keying (QPSK) signal. The 2-bit signals are retrieved from the acoustic domain with a global phase rotation of $蟺$, which is inherent in the process due to SBS. We also demonstrate full phase control over the retrieved data based on two different handles: by detuning slightly from the SBS resonance, or by changing the storage time in the memory scheme we can cover the full range $[0, 2蟺)$. At a cryogenic temperature of 3.9 K, we have increased readout efficiency as well as gained access to longer storage times, which results in a detectable signal at 140 ns. All in all, the work sets the cornerstone for optoacoustic memory schemes with phase-encoded data <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2410.05156v1-abstract-full').style.display = 'none'; document.getElementById('2410.05156v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 7 October, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2024. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">O.S. and J.H.M.C. contributed equally to this work</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2401.09155">arXiv:2401.09155</a> <span> [<a href="https://arxiv.org/pdf/2401.09155">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Frequency conversion of vortex states by chiral forward Brillouin scattering in twisted photonic crystal fibre </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zeng%2C+X">Xinglin Zeng</a>, <a href="/search/physics?searchtype=author&query=Russell%2C+P+S+J">Philip St. J. Russell</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2401.09155v1-abstract-short" style="display: inline;"> Optical vortex states-higher optical modes with helical phase progression and carrying orbital angular momentum-have been explored to increase the flexibility and capacity of optical fibres employed for example in mode-division-multiplexing, optical trapping and multimode imaging. A common requirement in such systems is high fidelity transfer of signals between different frequency bands and modes,… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2401.09155v1-abstract-full').style.display = 'inline'; document.getElementById('2401.09155v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2401.09155v1-abstract-full" style="display: none;"> Optical vortex states-higher optical modes with helical phase progression and carrying orbital angular momentum-have been explored to increase the flexibility and capacity of optical fibres employed for example in mode-division-multiplexing, optical trapping and multimode imaging. A common requirement in such systems is high fidelity transfer of signals between different frequency bands and modes, which for vortex modes is not so straightforward. Here we report intervortex conversion between backward-propagating circularly polarised vortex modes at one wavelength, using chiral flexural phonons excited by chiral forward stimulated Brillouin scattering at a different wavelength. The experiment is carried out using chiral photonic crystal fibre, which robustly preserves circular polarisation states. The chiral acoustic wave, which has the geometry of a spinning single-spiral corkscrew, provides the orbital angular momentum necessary to conserve angular momentum between the coupled optical vortex modes. The results open up new opportunities for interband optical frequency conversion and the manipulation of vortex states in both classical and quantum regimes. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2401.09155v1-abstract-full').style.display = 'none'; document.getElementById('2401.09155v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 17 January, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2401.05135">arXiv:2401.05135</a> <span> [<a href="https://arxiv.org/pdf/2401.05135">pdf</a>, <a href="https://arxiv.org/format/2401.05135">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> </div> </div> <p class="title is-5 mathjax"> All-optical nonlinear activation function based on stimulated Brillouin scattering </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Slinkov%2C+G">Grigorii Slinkov</a>, <a href="/search/physics?searchtype=author&query=Becker%2C+S">Steven Becker</a>, <a href="/search/physics?searchtype=author&query=Englund%2C+D">Dirk Englund</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2401.05135v1-abstract-short" style="display: inline;"> Photonic neural networks have demonstrated their potential over the past decades, but have not yet reached the full extent of their capabilities. One reason for this lies in an essential component - the nonlinear activation function, which ensures that the neural network can perform the required arbitrary nonlinear transformation. The desired all-optical nonlinear activation function is difficult… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2401.05135v1-abstract-full').style.display = 'inline'; document.getElementById('2401.05135v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2401.05135v1-abstract-full" style="display: none;"> Photonic neural networks have demonstrated their potential over the past decades, but have not yet reached the full extent of their capabilities. One reason for this lies in an essential component - the nonlinear activation function, which ensures that the neural network can perform the required arbitrary nonlinear transformation. The desired all-optical nonlinear activation function is difficult to realize, and as a result, most of the reported photonic neural networks rely on opto-electronic activation functions. Usually, the sacrifices made are the unique advantages of photonics, such as resource-efficient coherent and frequency-multiplexed information encoding. In addition, opto-electronic activation functions normally limit the photonic neural network depth by adding insertion losses. Here, we experimentally demonstrate an in-fiber photonic nonlinear activation function based on stimulated Brillouin scattering. Our design is coherent and frequency selective, making it suitable for multi-frequency neural networks. The optoacoustic activation function can be tuned continuously and all-optically between a variety of activation functions such as LeakyReLU, Sigmoid, and Quadratic. In addition, our design amplifies the input signal with gain as high as $20\,\mathrm{dB}$, compensating for insertion losses on the fly, and thus paving the way for deep optical neural networks. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2401.05135v1-abstract-full').style.display = 'none'; document.getElementById('2401.05135v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 10 January, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2311.06219">arXiv:2311.06219</a> <span> [<a href="https://arxiv.org/pdf/2311.06219">pdf</a>, <a href="https://arxiv.org/format/2311.06219">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> </div> </div> <p class="title is-5 mathjax"> High-speed coherent photonic random-access memory in long-lasting sound waves </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Geilen%2C+A">Andreas Geilen</a>, <a href="/search/physics?searchtype=author&query=Becker%2C+S">Steven Becker</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2311.06219v1-abstract-short" style="display: inline;"> In recent years, remarkable advances in photonic computing have highlighted the need for photonic memory, particularly high-speed and coherent random-access memory. Addressing the ongoing challenge of implementing photonic memories is required to fully harness the potential of photonic computing. A photonic-phononic memory based on stimulated Brillouin scattering is a possible solution as it coher… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2311.06219v1-abstract-full').style.display = 'inline'; document.getElementById('2311.06219v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2311.06219v1-abstract-full" style="display: none;"> In recent years, remarkable advances in photonic computing have highlighted the need for photonic memory, particularly high-speed and coherent random-access memory. Addressing the ongoing challenge of implementing photonic memories is required to fully harness the potential of photonic computing. A photonic-phononic memory based on stimulated Brillouin scattering is a possible solution as it coherently transfers optical information into sound waves at high-speed access times. Such an optoacoustic memory has shown great potential as it fulfils key requirements for high-performance optical random-access memory due to its coherence, on-chip compatibility, frequency selectivity, and high bandwidth. However, the storage time has so far been limited to a few nanoseconds due to the nanosecond decay of the acoustic wave. In this work, we experimentally enhance the intrinsic storage time of an optoacoustic memory by more than one order of magnitude and coherently retrieve optical information after a storage time of 120 ns. This is achieved by employing the optoacoustic memory in a highly nonlinear fiber at 4.2 K, increasing the intrinsic phonon lifetime by a factor of six. We demonstrate the capability of our scheme by measuring the initial and readout optical data pulse with a direct and double homodyne detection scheme. Finally, we analyze the dynamics of the optoacoustic memory at different cryogenic temperatures in the range of 4.2 K to 20 K and compare the findings to continuous wave measurements. The extended storage time is not only beneficial for photonic computing, but also for Brillouin applications that require long phonon lifetimes, such as optoacoustic filters, true-time delay networks, and synthesizers in microwave photonics. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2311.06219v1-abstract-full').style.display = 'none'; document.getElementById('2311.06219v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 10 November, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2023. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2309.01543">arXiv:2309.01543</a> <span> [<a href="https://arxiv.org/pdf/2309.01543">pdf</a>, <a href="https://arxiv.org/format/2309.01543">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1038/s41467-024-47053-6">10.1038/s41467-024-47053-6 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> An optoacoustic field-programmable perceptron for recurrent neural networks </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Becker%2C+S">Steven Becker</a>, <a href="/search/physics?searchtype=author&query=Englund%2C+D">Dirk Englund</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2309.01543v1-abstract-short" style="display: inline;"> A critical feature in signal processing is the ability to interpret correlations in time series signals, such as speech. Machine learning systems process this contextual information by tracking internal states in recurrent neural networks (RNNs), but these can cause memory and processor bottlenecks in applications from edge devices to data centers, motivating research into new analog inference arc… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2309.01543v1-abstract-full').style.display = 'inline'; document.getElementById('2309.01543v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2309.01543v1-abstract-full" style="display: none;"> A critical feature in signal processing is the ability to interpret correlations in time series signals, such as speech. Machine learning systems process this contextual information by tracking internal states in recurrent neural networks (RNNs), but these can cause memory and processor bottlenecks in applications from edge devices to data centers, motivating research into new analog inference architectures. But whereas photonic accelerators, in particular, have demonstrated big leaps in uni-directional feedforward deep neural network (DNN) inference, the bi-directional architecture of RNNs presents a unique challenge: the need for a short-term memory that (i) programmably transforms optical waveforms with phase coherence , (ii) minimizes added noise, and (iii) enables programmable readily scales to large neuron counts. Here, we address this challenge by introducing an optoacoustic recurrent operator (OREO) that simultaneously meets (i,ii,iii). Specifically, we experimentally demonstrate an OREO that contextualizes and computes the information carried by a sequence of optical pulses via acoustic waves. We show that the acoustic waves act as a link between the different optical pulses, capturing the optical information and using it to manipulate the subsequent operations. Our approach can be controlled completely optically on a pulse-by-pulse basis, offering simple reconfigurability for a use case-specific optimization. We use this feature to demonstrate a recurrent drop-out, which excludes optical input pulses from the recurrent operation. We furthermore apply OREO as an acceptor to recognize up-to $27$ patterns in a sequence of optical pulses. Finally, we introduce a DNN architecture that uses the OREO as bi-directional perceptrons to enable new classes of DNNs in coherent optical signal processing. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2309.01543v1-abstract-full').style.display = 'none'; document.getElementById('2309.01543v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 4 September, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2023. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2308.01009">arXiv:2308.01009</a> <span> [<a href="https://arxiv.org/pdf/2308.01009">pdf</a>, <a href="https://arxiv.org/format/2308.01009">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> </div> </div> <p class="title is-5 mathjax"> Brillouin light storage for 100 pulse widths </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Jaksch%2C+K">Kevin Jaksch</a>, <a href="/search/physics?searchtype=author&query=Piotrowski%2C+J">Johannes Piotrowski</a>, <a href="/search/physics?searchtype=author&query=Merklein%2C+M">Moritz Merklein</a>, <a href="/search/physics?searchtype=author&query=Schmidt%2C+M+K">Mikolaj K. Schmidt</a>, <a href="/search/physics?searchtype=author&query=Vu%2C+K">Khu Vu</a>, <a href="/search/physics?searchtype=author&query=Ma%2C+P">Pan Ma</a>, <a href="/search/physics?searchtype=author&query=Madden%2C+S">Stephen Madden</a>, <a href="/search/physics?searchtype=author&query=Steel%2C+M+J">Michael J. Steel</a>, <a href="/search/physics?searchtype=author&query=Poulton%2C+C+G">Christopher G. Poulton</a>, <a href="/search/physics?searchtype=author&query=Eggleton%2C+B+J">Benjamin J. Eggleton</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2308.01009v1-abstract-short" style="display: inline;"> Signal processing based on stimulated Brillouin scattering (SBS) is limited by the narrow linewidth of the optoacoustic response, which confines many Brillouin applications to continuous wave signals or optical pulses longer than several nanoseconds. In this work, we experimentally demonstrate Brillouin interactions at the 150 ps time scale and a delay for a record 15 ns which corresponds to a del… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2308.01009v1-abstract-full').style.display = 'inline'; document.getElementById('2308.01009v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2308.01009v1-abstract-full" style="display: none;"> Signal processing based on stimulated Brillouin scattering (SBS) is limited by the narrow linewidth of the optoacoustic response, which confines many Brillouin applications to continuous wave signals or optical pulses longer than several nanoseconds. In this work, we experimentally demonstrate Brillouin interactions at the 150 ps time scale and a delay for a record 15 ns which corresponds to a delay of 100 pulse widths. This breakthrough experimental result was enabled by the high local gain of the chalcogenide waveguides as the optoacoustic interaction length reduces with pulse width. We successfully transfer 150ps-long pulses to traveling acoustic waves within a Brillouin-based memory setup. The information encoded in the optical pulses is stored for 15 ns in the acoustic field. We show the retrieval of eight amplitude levels, multiple consecutive pulses and low distortion in pulse shape. The extension of Brillouin-based storage to the ultra-short pulse regime is an important step for the realisation of practical Brillouin-based delay lines and other optical processing applications. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2308.01009v1-abstract-full').style.display = 'none'; document.getElementById('2308.01009v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 2 August, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">6 pages, 6 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2306.14341">arXiv:2306.14341</a> <span> [<a href="https://arxiv.org/pdf/2306.14341">pdf</a>, <a href="https://arxiv.org/format/2306.14341">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Eavesdropper localization for quantum and classical channels via nonlinear scattering </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Popp%2C+A">Alexandra Popp</a>, <a href="/search/physics?searchtype=author&query=Sedlmeir%2C+F">Florian Sedlmeir</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Marquardt%2C+C">Christoph Marquardt</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2306.14341v1-abstract-short" style="display: inline;"> Optical fiber networks are part of important critical infrastructure and known to be prone to eavesdropping attacks. Hence cryptographic methods have to be used to protect communication. Quantum key distribution (QKD), at its core, offers information theoretical security based on the laws of physics. In deployments one has to take into account practical security and resilience. The latter includes… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2306.14341v1-abstract-full').style.display = 'inline'; document.getElementById('2306.14341v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2306.14341v1-abstract-full" style="display: none;"> Optical fiber networks are part of important critical infrastructure and known to be prone to eavesdropping attacks. Hence cryptographic methods have to be used to protect communication. Quantum key distribution (QKD), at its core, offers information theoretical security based on the laws of physics. In deployments one has to take into account practical security and resilience. The latter includes the localization of a possible eavesdropper after an anomaly has been detected by the QKD system to avoid denial-of-service. Here, we present a novel approach to eavesdropper location that can be employed in quantum as well as classical channels using stimulated Brillouin scattering. The tight localization of the acoustic wave inside the fiber channel using correlated pump and probe waves allows to discover the coordinates of a potential threat within centimeters. We demonstrate that our approach outperforms conventional OTDR in the task of localizing an evanescent outcoupling of 1% with cm precision inside standard optical fibers. The system is furthermore able to clearly distinguish commercially available standard SMF28 from different manufacturers, paving the way for fingerprinted fibers in high security environments. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2306.14341v1-abstract-full').style.display = 'none'; document.getElementById('2306.14341v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 25 June, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2023. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2305.19823">arXiv:2305.19823</a> <span> [<a href="https://arxiv.org/pdf/2305.19823">pdf</a>, <a href="https://arxiv.org/format/2305.19823">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Optoacoustic cooling of traveling hypersound waves </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Mart%C3%ADnez%2C+L+B">Laura Bl谩zquez Mart铆nez</a>, <a href="/search/physics?searchtype=author&query=Wiedemann%2C+P">Philipp Wiedemann</a>, <a href="/search/physics?searchtype=author&query=Zhu%2C+C">Changlong Zhu</a>, <a href="/search/physics?searchtype=author&query=Geilen%2C+A">Andreas Geilen</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2305.19823v1-abstract-short" style="display: inline;"> We experimentally demonstrate optoacoustic cooling via stimulated Brillouin-Mandelstam scattering in a 50 cm-long tapered photonic crystal fiber. For a 7.38 GHz acoustic mode, a cooling rate of 219 K from room temperature has been achieved. As anti-Stokes and Stokes Brillouin processes naturally break the symmetry of phonon cooling and heating, resolved sideband schemes are not necessary. The expe… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.19823v1-abstract-full').style.display = 'inline'; document.getElementById('2305.19823v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2305.19823v1-abstract-full" style="display: none;"> We experimentally demonstrate optoacoustic cooling via stimulated Brillouin-Mandelstam scattering in a 50 cm-long tapered photonic crystal fiber. For a 7.38 GHz acoustic mode, a cooling rate of 219 K from room temperature has been achieved. As anti-Stokes and Stokes Brillouin processes naturally break the symmetry of phonon cooling and heating, resolved sideband schemes are not necessary. The experiments pave the way to explore the classical to quantum transition for macroscopic objects and could enable new quantum technologies in terms of storage and repeater schemes. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.19823v1-abstract-full').style.display = 'none'; document.getElementById('2305.19823v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 31 May, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">5 pages, 3 figures, L. B. M., P. W. and C. Z. contributed equally to this work</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2301.07592">arXiv:2301.07592</a> <span> [<a href="https://arxiv.org/pdf/2301.07592">pdf</a>, <a href="https://arxiv.org/format/2301.07592">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/OE.486550">10.1364/OE.486550 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Spin-orbit interaction in nanofiber-based Brillouin scattering </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zerbib%2C+M">Maxime Zerbib</a>, <a href="/search/physics?searchtype=author&query=Romanet%2C+M">Maxime Romanet</a>, <a href="/search/physics?searchtype=author&query=Sylvestre%2C+T">Thibaut Sylvestre</a>, <a href="/search/physics?searchtype=author&query=Wolff%2C+C">Christian Wolff</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Beugnot%2C+J">Jean-Charles Beugnot</a>, <a href="/search/physics?searchtype=author&query=Huy%2C+K+P">Kien Phan Huy</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2301.07592v1-abstract-short" style="display: inline;"> Angular momentum is an important physical property that plays a key role in light-matter interactions such as spin-orbit interaction. Here, we investigate theoretically and experimentally the spin-orbit interaction between a circularly polarized optical (spin) and a transverse vortex acoustic wave (orbital) using Brillouin backscattering in a silica optical nanofiber. We specifically explore the s… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2301.07592v1-abstract-full').style.display = 'inline'; document.getElementById('2301.07592v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2301.07592v1-abstract-full" style="display: none;"> Angular momentum is an important physical property that plays a key role in light-matter interactions such as spin-orbit interaction. Here, we investigate theoretically and experimentally the spin-orbit interaction between a circularly polarized optical (spin) and a transverse vortex acoustic wave (orbital) using Brillouin backscattering in a silica optical nanofiber. We specifically explore the state of polarization of Brillouin backscattering induced by the TR21 torso-radial vortex acoustic mode that carries an orbital angular momentum. Using a full-vectorial theoretical model, we predict and observe two operating regimes for which the backscattered Brillouin signal is either depolarized or circularly polarized depending on the input pump polarization. We demonstrate that when the pump is circularly polarized and thus carries a spin angular momentum, the backscattered signal undergoes a handedness reversal of circular polarization due to optoacoustic spin-orbit interaction and the conservation of overall angular momentum. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2301.07592v1-abstract-full').style.display = 'none'; document.getElementById('2301.07592v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 18 January, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2023. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2208.04814">arXiv:2208.04814</a> <span> [<a href="https://arxiv.org/pdf/2208.04814">pdf</a>, <a href="https://arxiv.org/format/2208.04814">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Exploring extreme thermodynamics in nanoliter volumes through stimulated Brillouin-Mandelstam scattering </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Geilen%2C+A">Andreas Geilen</a>, <a href="/search/physics?searchtype=author&query=Popp%2C+A">Alexandra Popp</a>, <a href="/search/physics?searchtype=author&query=Das%2C+D">Debayan Das</a>, <a href="/search/physics?searchtype=author&query=Junaid%2C+S">Saher Junaid</a>, <a href="/search/physics?searchtype=author&query=Poulton%2C+C+G">Christopher G. Poulton</a>, <a href="/search/physics?searchtype=author&query=Chemnitz%2C+M">Mario Chemnitz</a>, <a href="/search/physics?searchtype=author&query=Marquardt%2C+C">Christoph Marquardt</a>, <a href="/search/physics?searchtype=author&query=Schmidt%2C+M+A">Markus A. Schmidt</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2208.04814v1-abstract-short" style="display: inline;"> Examining the physical properties of materials - particularly of toxic liquids - under a wide range of thermodynamic states is a challenging problem due to the extreme conditions the material has to be exposed to. Such temperature and pressure regimes, which result in a change of refractive index and sound velocity can be accessed by optoacoustic interactions such as Brillouin-Mandelstam scatterin… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2208.04814v1-abstract-full').style.display = 'inline'; document.getElementById('2208.04814v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2208.04814v1-abstract-full" style="display: none;"> Examining the physical properties of materials - particularly of toxic liquids - under a wide range of thermodynamic states is a challenging problem due to the extreme conditions the material has to be exposed to. Such temperature and pressure regimes, which result in a change of refractive index and sound velocity can be accessed by optoacoustic interactions such as Brillouin-Mandelstam scattering. Here we experimentally demonstrate Brillouin-Mandelstam measurements of nanoliter volumes of liquids in extreme thermodynamic regimes. We use a fully-sealed liquid-core optical fiber containing carbon disulfide; within this waveguide, which exhibits tight optoacoustic confinement and a high Brillouin gain of (32.2 $\pm$ 0.8) 1/(Wm), we are able to conduct spatially resolved measurements of the Brillouin frequency shift. Knowledge of the local Brillouin response enables us to control the temperature and pressure independently over a wide range. We observe and measure the material properties of the liquid core at very large positive pressures (above 1000 bar), substantial negative pressures (below -300 bar) and we explore the isobaric and isochoric regimes. The extensive thermodynamic control allows the tunability of the Brillouin frequency shift of more than 40% using only minute volumes of liquid. This work opens the way for future studies of liquids under a variety of conventionally hard-to-reach conditions. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2208.04814v1-abstract-full').style.display = 'none'; document.getElementById('2208.04814v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 9 August, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2204.11971">arXiv:2204.11971</a> <span> [<a href="https://arxiv.org/pdf/2204.11971">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Optical vortex Brillouin laser </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zeng%2C+X">Xinglin Zeng</a>, <a href="/search/physics?searchtype=author&query=Russell%2C+P+S+J">Philip St. J. Russell</a>, <a href="/search/physics?searchtype=author&query=Chen%2C+Y">Yang Chen</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+Z">Zheqi Wang</a>, <a href="/search/physics?searchtype=author&query=Wong%2C+G+K+L">Gordon K. L. Wong</a>, <a href="/search/physics?searchtype=author&query=Roth%2C+P">Paul Roth</a>, <a href="/search/physics?searchtype=author&query=Frosz%2C+M+H">Michael H. Frosz</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2204.11971v1-abstract-short" style="display: inline;"> Optical vortices, which have been extensively studied over the last decades, offer an additional degree of freedom useful in many applications, such as optical tweezers and quantum control. Stimulated Brillouin scattering, providing a narrow linewidth and a strong nonlinear response, has been used to realise quasi-continuous wave (CW) lasers. Here, we report stable oscillation of optical vortices… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2204.11971v1-abstract-full').style.display = 'inline'; document.getElementById('2204.11971v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2204.11971v1-abstract-full" style="display: none;"> Optical vortices, which have been extensively studied over the last decades, offer an additional degree of freedom useful in many applications, such as optical tweezers and quantum control. Stimulated Brillouin scattering, providing a narrow linewidth and a strong nonlinear response, has been used to realise quasi-continuous wave (CW) lasers. Here, we report stable oscillation of optical vortices and acoustic modes in a Brillouin laser based on chiral photonic crystal fibre, which robustly supports helical Bloch modes (HBMs) that carry circularly-polarized optical vortex and display circular birefringence. We implement a narrow-linewidth Brillouin fibre laser that stably emits 1st- and 2nd-order vortex-carrying HBMs. Angular momentum conservation selection rules dictate that pump and backward Brillouin signals have opposite topological charge and spin. Additionally, we show that when the chiral PCF is placed within a laser ring cavity, the linewidth-narrowing associated with lasing permits the peak of the Brillouin gain that corresponds to acoustic mode to be measured with resolution of 10 kHz and accuracy of 520 kHz. The results pave the way to a new generation of vortex-carrying SBS systems with applications in quantum information processing, vortex-carrying nonreciprocal systems. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2204.11971v1-abstract-full').style.display = 'none'; document.getElementById('2204.11971v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 25 April, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2203.03680">arXiv:2203.03680</a> <span> [<a href="https://arxiv.org/pdf/2203.03680">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> </div> </div> <p class="title is-5 mathjax"> Nonreciprocal vortex isolator by stimulated Brillouin scattering in chiral photonic crystal fibre </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zeng%2C+X">Xinglin Zeng</a>, <a href="/search/physics?searchtype=author&query=Russell%2C+P+S+J">Philip St. J. Russell</a>, <a href="/search/physics?searchtype=author&query=Wolff%2C+C">Christian Wolff</a>, <a href="/search/physics?searchtype=author&query=Frosz%2C+M+H">Michael H. Frosz</a>, <a href="/search/physics?searchtype=author&query=Wong%2C+G+K+L">Gordon K. L. Wong</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2203.03680v1-abstract-short" style="display: inline;"> Optical non-reciprocity, which breaks the symmetry between forward and backward propagating optical waves, has become vital in photonic systems and enables many key devices, such as optical isolators, circulators and optical routers. Most conventional optical isolators involve magneto-optic materials, but devices based on optical nonlinearities, optomechanically induced transparency and stimulated… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2203.03680v1-abstract-full').style.display = 'inline'; document.getElementById('2203.03680v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2203.03680v1-abstract-full" style="display: none;"> Optical non-reciprocity, which breaks the symmetry between forward and backward propagating optical waves, has become vital in photonic systems and enables many key devices, such as optical isolators, circulators and optical routers. Most conventional optical isolators involve magneto-optic materials, but devices based on optical nonlinearities, optomechanically induced transparency and stimulated Brillouin scattering (SBS) have also been demonstrated. So far, however, they have only been implemented for linearly or randomly polarized LP01-like fundamental modes. Here we report a light-driven nonreciprocal isolator for optical vortex modes, based on topology-selective SBS in chiral photonic crystal fibre. The device can be reconfigured as an amplifier or an isolator by adjusting the frequency of the control signal. The experimental results show vortex isolation of 22 dB, which is at the state-of-the-art in fundamental mode isolators using SBS. This unique device may find applications in optical communications, fibre lasers, quantum information processing and optical tweezers. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2203.03680v1-abstract-full').style.display = 'none'; document.getElementById('2203.03680v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 7 March, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2111.05289">arXiv:2111.05289</a> <span> [<a href="https://arxiv.org/pdf/2111.05289">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/PRJ.443706">10.1364/PRJ.443706 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Stimulated Brillouin scattering in chiral photonic crystal fiber </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zeng%2C+X">Xinglin Zeng</a>, <a href="/search/physics?searchtype=author&query=He%2C+W">Wenbin He</a>, <a href="/search/physics?searchtype=author&query=Frosz%2C+M+H">Micahel H. Frosz</a>, <a href="/search/physics?searchtype=author&query=Geilen%2C+A">Andreas Geilen</a>, <a href="/search/physics?searchtype=author&query=Roth%2C+P">Paul Roth</a>, <a href="/search/physics?searchtype=author&query=Wong%2C+G+K+L">Gordon K. L. Wong</a>, <a href="/search/physics?searchtype=author&query=Russell%2C+P+S+J">Philip St. J. Russell</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2111.05289v1-abstract-short" style="display: inline;"> Stimulated Brillouin scattering (SBS) has many applications, for example, in sensing, microwave photonics and signal processing. Here we report the first experimental study of SBS in chiral photonic crystal fiber (PCF), which displays optical activity and robustly maintains circular polarization states against external perturbations. As a result, circularly polarized pump light is cleanly back-sca… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2111.05289v1-abstract-full').style.display = 'inline'; document.getElementById('2111.05289v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2111.05289v1-abstract-full" style="display: none;"> Stimulated Brillouin scattering (SBS) has many applications, for example, in sensing, microwave photonics and signal processing. Here we report the first experimental study of SBS in chiral photonic crystal fiber (PCF), which displays optical activity and robustly maintains circular polarization states against external perturbations. As a result, circularly polarized pump light is cleanly back-scattered into a Stokes signal with the orthogonal circular polarization state, as is required by angular momentum conservation. By comparison, untwisted PCF generates a Stokes signal with an unpredictable polarization state, owing to its high sensitivity to external perturbations. We use chiral PCF to realize a circularly polarized continuous-wave Brillouin laser. The results pave the way to a new generation of stable circularly polarized SBS systems with applications in quantum manipulation, optical tweezers, optical gyroscopes and fiber sensors. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2111.05289v1-abstract-full').style.display = 'none'; document.getElementById('2111.05289v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 9 November, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2021. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Photonics Research Vol. 10, Issue 3, pp. 711-718 (2022) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2103.05732">arXiv:2103.05732</a> <span> [<a href="https://arxiv.org/pdf/2103.05732">pdf</a>, <a href="https://arxiv.org/format/2103.05732">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/OL.424701">10.1364/OL.424701 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Picosecond acoustic dynamics in stimulated Brillouin scattering </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Piotrowski%2C+J">Johannes Piotrowski</a>, <a href="/search/physics?searchtype=author&query=Schmidt%2C+M+K">Miko艂aj K. Schmidt</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Poulton%2C+C+G">Christopher G. Poulton</a>, <a href="/search/physics?searchtype=author&query=Steel%2C+M">Michael Steel</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2103.05732v1-abstract-short" style="display: inline;"> Recent experiments demonstrating storage of optical pulses in acoustic phonons based on stimulated Brillouin scattering raise a number of questions about the spectral and temporal capacities of such protocols and the limitations of the theoretical frameworks routinely used to describe them. In this work, we consider the dynamics of photon-phonon scattering induced by optical pulses with temporal w… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2103.05732v1-abstract-full').style.display = 'inline'; document.getElementById('2103.05732v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2103.05732v1-abstract-full" style="display: none;"> Recent experiments demonstrating storage of optical pulses in acoustic phonons based on stimulated Brillouin scattering raise a number of questions about the spectral and temporal capacities of such protocols and the limitations of the theoretical frameworks routinely used to describe them. In this work, we consider the dynamics of photon-phonon scattering induced by optical pulses with temporal widths comparable to the period of acoustic oscillations. We revisit the widely adopted classical formalism of coupled modes and demonstrate its breakdown. We propose a simple extension to generalise the formulation and find potentially measurable consequences in the dynamics of Brillouin experiments involving ultra-short pulses. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2103.05732v1-abstract-full').style.display = 'none'; document.getElementById('2103.05732v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 9 March, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2021. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">5 pages, 3 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1904.13167">arXiv:1904.13167</a> <span> [<a href="https://arxiv.org/pdf/1904.13167">pdf</a>, <a href="https://arxiv.org/format/1904.13167">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Coherently refreshed acoustic phonons for extended light storage </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Merklein%2C+M">Moritz Merklein</a>, <a href="/search/physics?searchtype=author&query=Wolff%2C+C">Christian Wolff</a>, <a href="/search/physics?searchtype=author&query=Vu%2C+K">Khu Vu</a>, <a href="/search/physics?searchtype=author&query=Ma%2C+P">Pan Ma</a>, <a href="/search/physics?searchtype=author&query=Madden%2C+S+J">Stephen J. Madden</a>, <a href="/search/physics?searchtype=author&query=Eggleton%2C+B+J">Benjamin J. Eggleton</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1904.13167v1-abstract-short" style="display: inline;"> Acoustic waves can serve as memory for optical information, however, acoustic phonons in the GHz regime decay on the nanosecond timescale. Usually this is dominated by intrinsic acoustic loss due to inelastic scattering of the acoustic waves and thermal phonons. Here we show a way to counteract the intrinsic acoustic decay of the phonons in a waveguide by resonantly reinforcing the acoustic wave v… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1904.13167v1-abstract-full').style.display = 'inline'; document.getElementById('1904.13167v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1904.13167v1-abstract-full" style="display: none;"> Acoustic waves can serve as memory for optical information, however, acoustic phonons in the GHz regime decay on the nanosecond timescale. Usually this is dominated by intrinsic acoustic loss due to inelastic scattering of the acoustic waves and thermal phonons. Here we show a way to counteract the intrinsic acoustic decay of the phonons in a waveguide by resonantly reinforcing the acoustic wave via synchronized optical pulses. This scheme overcomes the previous constraints of phonon-based optical signal processing for light storage and memory. We experimentally demonstrate on-chip storage up to 40 ns, four times the intrinsic acoustic lifetime in the waveguide. We confirm the coherence of the scheme by detecting the phase of the delayed optical signal after 40 ns using homodyne detection. Through theoretical considerations we anticipate that this concept allows for storage times up to microseconds within realistic experimental limitations while maintaining a GHz bandwidth of the optical signal. The refreshed phonon-based light storage removes the usual bandwidth-delay product limitations of e.g. slow-light schemes. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1904.13167v1-abstract-full').style.display = 'none'; document.getElementById('1904.13167v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 30 April, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">6 pages, 5 figures, BS and MM contributed equally</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1809.07160">arXiv:1809.07160</a> <span> [<a href="https://arxiv.org/pdf/1809.07160">pdf</a>, <a href="https://arxiv.org/format/1809.07160">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/JOSAB.36.000146">10.1364/JOSAB.36.000146 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> On-chip correlation-based Brillouin sensing: design, experiment and simulation </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zarifi%2C+A">Atiyeh Zarifi</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Merklein%2C+M">Moritz Merklein</a>, <a href="/search/physics?searchtype=author&query=Liu%2C+Y">Yang Liu</a>, <a href="/search/physics?searchtype=author&query=Morrison%2C+B">Blair Morrison</a>, <a href="/search/physics?searchtype=author&query=Casas-Bedoya%2C+A">Alvaro Casas-Bedoya</a>, <a href="/search/physics?searchtype=author&query=Ren%2C+G">Gang Ren</a>, <a href="/search/physics?searchtype=author&query=Nguyen%2C+T+G">Thach G. Nguyen</a>, <a href="/search/physics?searchtype=author&query=Vu%2C+K">Khu Vu</a>, <a href="/search/physics?searchtype=author&query=Choi%2C+D">Duk-Yong Choi</a>, <a href="/search/physics?searchtype=author&query=Mitchell%2C+A">Arnan Mitchell</a>, <a href="/search/physics?searchtype=author&query=Madden%2C+S+J">Stephen J. Madden</a>, <a href="/search/physics?searchtype=author&query=Eggleton%2C+B+J">Benjamin J. Eggleton</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1809.07160v1-abstract-short" style="display: inline;"> Wavelength-scale SBS waveguides are enabling novel on-chip functionalities. The micro- and nano-scale SBS structures and the complexity of the SBS waveguides require a characterization technique to monitor the local geometry-dependent SBS responses along the waveguide. In this work, we experimentally demonstrate detection of longitudinal features down to 200$渭$m on a silicon-chalcogenide waveguide… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1809.07160v1-abstract-full').style.display = 'inline'; document.getElementById('1809.07160v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1809.07160v1-abstract-full" style="display: none;"> Wavelength-scale SBS waveguides are enabling novel on-chip functionalities. The micro- and nano-scale SBS structures and the complexity of the SBS waveguides require a characterization technique to monitor the local geometry-dependent SBS responses along the waveguide. In this work, we experimentally demonstrate detection of longitudinal features down to 200$渭$m on a silicon-chalcogenide waveguide using the Brillouin optical correlation domain analysis (BOCDA) technique. We provide simulation and analysis on how multiple acoustic and optical modes and geometrical variations influence the Brillouin spectrum. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1809.07160v1-abstract-full').style.display = 'none'; document.getElementById('1809.07160v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 29 August, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">8 pages, 6 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1806.00146">arXiv:1806.00146</a> <span> [<a href="https://arxiv.org/pdf/1806.00146">pdf</a>, <a href="https://arxiv.org/format/1806.00146">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> On-chip broadband non-reciprocal light storage </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Merklein%2C+M">Moritz Merklein</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Vu%2C+K">Khu Vu</a>, <a href="/search/physics?searchtype=author&query=Ma%2C+P">Pan Ma</a>, <a href="/search/physics?searchtype=author&query=Madden%2C+S+J">Stephen J. Madden</a>, <a href="/search/physics?searchtype=author&query=Eggleton%2C+B+J">Benjamin J. Eggleton</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1806.00146v2-abstract-short" style="display: inline;"> Breaking the symmetry between forward and backward propagating optical modes is of fundamental scientific interest and enables crucial functionalities, such as isolators, circulators, and duplex communication systems. Whereas there has been progress in achieving optical isolation on-chip, integrated broadband non-reciprocal signal processing functionalities that enable transmitting and receiving v… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1806.00146v2-abstract-full').style.display = 'inline'; document.getElementById('1806.00146v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1806.00146v2-abstract-full" style="display: none;"> Breaking the symmetry between forward and backward propagating optical modes is of fundamental scientific interest and enables crucial functionalities, such as isolators, circulators, and duplex communication systems. Whereas there has been progress in achieving optical isolation on-chip, integrated broadband non-reciprocal signal processing functionalities that enable transmitting and receiving via the same low-loss planar waveguide, without altering the frequency or mode of the signal, remain elusive. Here, we demonstrate a non-reciprocal delay scheme based on the uni-directional transfer of optical data pulses to acoustic waves in a chip-based integration platform. We experimentally demonstrate that this scheme is not impacted by simultaneously counter-propagating optical signals. Furthermore, we achieve a bandwidth more than an order of magnitude broader than the intrinsic opto-acoustic linewidth, linear operation for a wide range of signal powers, and importantly, show that this scheme is wavelength preserving and avoids complicated multi-mode structures.. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1806.00146v2-abstract-full').style.display = 'none'; document.getElementById('1806.00146v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 August, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 31 May, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">8 pages, 6 figures, Moritz Merklein and Birgit Stiller contributed equally to this work</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1806.00140">arXiv:1806.00140</a> <span> [<a href="https://arxiv.org/pdf/1806.00140">pdf</a>, <a href="https://arxiv.org/format/1806.00140">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/OL.43.003493">10.1364/OL.43.003493 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Brillouin spectroscopy of a hybrid silicon-chalcogenide waveguide with geometrical variations </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zarifi%2C+A">Atiyeh Zarifi</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Merklein%2C+M">Moritz Merklein</a>, <a href="/search/physics?searchtype=author&query=Liu%2C+Y">Yang Liu</a>, <a href="/search/physics?searchtype=author&query=Morrison%2C+B">Blair Morrison</a>, <a href="/search/physics?searchtype=author&query=Casas-Bedoya%2C+A">Alvaro Casas-Bedoya</a>, <a href="/search/physics?searchtype=author&query=Ren%2C+G">Gang Ren</a>, <a href="/search/physics?searchtype=author&query=Nguyen%2C+T+G">Thach G. Nguyen</a>, <a href="/search/physics?searchtype=author&query=Vu%2C+K">Khu Vu</a>, <a href="/search/physics?searchtype=author&query=Choi%2C+D">Duk-Yong Choi</a>, <a href="/search/physics?searchtype=author&query=Mitchell%2C+A">Arnan Mitchell</a>, <a href="/search/physics?searchtype=author&query=Madden%2C+S+J">Stephen J. Madden</a>, <a href="/search/physics?searchtype=author&query=Eggleton%2C+B+J">Benjamin J. Eggleton</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1806.00140v1-abstract-short" style="display: inline;"> Recent advances in design and fabrication of photonic-phononic waveguides have enabled stimulated Brillouin scattering (SBS) in silicon-based platforms, such as under-etched silicon waveguides and hybrid waveguides. Due to the sophisticated design and more importantly high sensitivity of the Brillouin resonances to geometrical variations in micro- and nano-scale structures, it is necessary to have… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1806.00140v1-abstract-full').style.display = 'inline'; document.getElementById('1806.00140v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1806.00140v1-abstract-full" style="display: none;"> Recent advances in design and fabrication of photonic-phononic waveguides have enabled stimulated Brillouin scattering (SBS) in silicon-based platforms, such as under-etched silicon waveguides and hybrid waveguides. Due to the sophisticated design and more importantly high sensitivity of the Brillouin resonances to geometrical variations in micro- and nano-scale structures, it is necessary to have access to the localized opto-acoustic response along those waveguides to monitor their uniformity and maximize their interaction strength. In this work, we design and fabricate photonic-phononic waveguides with a deliberate width variation on a hybrid silicon-chalcogenide photonic chip and confirm the effect of the geometrical variation on the localized Brillouin response using a distributed Brillouin measurement. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1806.00140v1-abstract-full').style.display = 'none'; document.getElementById('1806.00140v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 31 May, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">5 pages, 4 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1804.08799">arXiv:1804.08799</a> <span> [<a href="https://arxiv.org/pdf/1804.08799">pdf</a>, <a href="https://arxiv.org/format/1804.08799">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/OL.43.004321">10.1364/OL.43.004321 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> On-chip multi-stage optical delay based on cascaded Brillouin light storage </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Merklein%2C+M">Moritz Merklein</a>, <a href="/search/physics?searchtype=author&query=Wolff%2C+C">Christian Wolff</a>, <a href="/search/physics?searchtype=author&query=Vu%2C+K">Khu Vu</a>, <a href="/search/physics?searchtype=author&query=Ma%2C+P">Pan Ma</a>, <a href="/search/physics?searchtype=author&query=Poulton%2C+C+G">Christopher G. Poulton</a>, <a href="/search/physics?searchtype=author&query=Madden%2C+S+J">Stephen J. Madden</a>, <a href="/search/physics?searchtype=author&query=Eggleton%2C+B+J">Benjamin J. Eggleton</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1804.08799v1-abstract-short" style="display: inline;"> Storing and delaying optical signals plays a crucial role in data centers, phased array antennas, communication and future computing architectures. Here, we show a delay scheme based on cascaded Brillouin light storage, that achieves multi-stage delay at arbitrary positions within a photonic integrated circuit. Importantly these multiple resonant transfers between the optical and acoustic domain a… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1804.08799v1-abstract-full').style.display = 'inline'; document.getElementById('1804.08799v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1804.08799v1-abstract-full" style="display: none;"> Storing and delaying optical signals plays a crucial role in data centers, phased array antennas, communication and future computing architectures. Here, we show a delay scheme based on cascaded Brillouin light storage, that achieves multi-stage delay at arbitrary positions within a photonic integrated circuit. Importantly these multiple resonant transfers between the optical and acoustic domain are controlled solely via external optical control pulses, allowing cascading of the delay without the need of aligning multiple structural resonances along the optical circuit. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1804.08799v1-abstract-full').style.display = 'none'; document.getElementById('1804.08799v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 23 April, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">5 pages, 5 figures, Birgit Stiller and Moritz Merklein contributed equally to this work</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1803.08626">arXiv:1803.08626</a> <span> [<a href="https://arxiv.org/pdf/1803.08626">pdf</a>, <a href="https://arxiv.org/format/1803.08626">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Crosstalk-free multi-wavelength coherent light storage via Brillouin interaction </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Merklein%2C+M">Moritz Merklein</a>, <a href="/search/physics?searchtype=author&query=Vu%2C+K">Khu Vu</a>, <a href="/search/physics?searchtype=author&query=Ma%2C+P">Pan Ma</a>, <a href="/search/physics?searchtype=author&query=Madden%2C+S+J">Stephen J. Madden</a>, <a href="/search/physics?searchtype=author&query=Poulton%2C+C+G">Christopher G. Poulton</a>, <a href="/search/physics?searchtype=author&query=Eggleton%2C+B+J">Benjamin J. Eggleton</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1803.08626v2-abstract-short" style="display: inline;"> Stimulated Brillouin scattering drives a coherent interaction between optical signals and acoustic phonons and this effect can be used for storing optical information in acoustic waves. An important consideration arises when multiple optical frequencies are simultaneously employed in the Brillouin process: in this case the acoustic phonons that are addressed by each optical wavelength can be separ… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1803.08626v2-abstract-full').style.display = 'inline'; document.getElementById('1803.08626v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1803.08626v2-abstract-full" style="display: none;"> Stimulated Brillouin scattering drives a coherent interaction between optical signals and acoustic phonons and this effect can be used for storing optical information in acoustic waves. An important consideration arises when multiple optical frequencies are simultaneously employed in the Brillouin process: in this case the acoustic phonons that are addressed by each optical wavelength can be separated by frequencies far smaller than the acoustic phonon linewidth, potentially leading to crosstalk between the optical modes. Here we extend the concept of Brillouin-based light storage to multiple wavelength channels. We experimentally and theoretically show that the accumulated phase mismatch over the length of the spatially extended phonons allows each optical wavelength channel to address a distinct phonon mode, ensuring negligible crosstalk, even if the phonons overlap in frequency. Moreover, we demonstrate that the strict phase matching condition enables the preservation of the coherence of the opto-acoustic transfer at closely spaced multiple acoustic frequencies. This particular phase-mismatch for broad-bandwidth pulses has far-reaching implications allowing dense wavelength multiplexing in Brillouin-based light storage, multi-frequency Brillouin sensing, multi-wavelength Brillouin lasers, parallel microwave processing and quantum photon-phonon interactions. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1803.08626v2-abstract-full').style.display = 'none'; document.getElementById('1803.08626v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 4 October, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 22 March, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">11 pages, 12 figures, Birgit Stiller and Moritz Merklein contributed equally to this work</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1707.09684">arXiv:1707.09684</a> <span> [<a href="https://arxiv.org/pdf/1707.09684">pdf</a>, <a href="https://arxiv.org/format/1707.09684">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Highly localized Brillouin scattering response in a photonic integrated circuit </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zarifi%2C+A">Atiyeh Zarifi</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Merklein%2C+M">Moritz Merklein</a>, <a href="/search/physics?searchtype=author&query=Li%2C+N">Neuton Li</a>, <a href="/search/physics?searchtype=author&query=Vu%2C+K">Khu Vu</a>, <a href="/search/physics?searchtype=author&query=Choi%2C+D">Duk-Yong Choi</a>, <a href="/search/physics?searchtype=author&query=Ma%2C+P">Pan Ma</a>, <a href="/search/physics?searchtype=author&query=Madden%2C+S+J">Stephen J. Madden</a>, <a href="/search/physics?searchtype=author&query=Eggleton%2C+B+J">Benjamin J. Eggleton</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1707.09684v1-abstract-short" style="display: inline;"> The interaction of optical and acoustic waves via stimulated Brillouin scattering (SBS) has recently reached on-chip platforms, which has opened new fields of applications ranging from integrated microwave photonics and on-chip narrow-linewidth lasers, to phonon-based optical delay and signal processing schemes. Since SBS is an effect that scales exponentially with interaction length, on-chip impl… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1707.09684v1-abstract-full').style.display = 'inline'; document.getElementById('1707.09684v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1707.09684v1-abstract-full" style="display: none;"> The interaction of optical and acoustic waves via stimulated Brillouin scattering (SBS) has recently reached on-chip platforms, which has opened new fields of applications ranging from integrated microwave photonics and on-chip narrow-linewidth lasers, to phonon-based optical delay and signal processing schemes. Since SBS is an effect that scales exponentially with interaction length, on-chip implementation on a short length scale is challenging, requiring carefully designed waveguides with optimized opto-acoustic overlap. In this work, we use the principle of Brillouin optical correlation domain analysis (BOCDA) to locally measure the SBS spectrum with high spatial resolution of 800 渭m and perform a distributed measurement of the Brillouin spectrum along a spiral waveguide in a photonic integrated circuit (PIC). This approach gives access to local opto-acoustic properties of the waveguides, including the Brillouin frequency shift (BFS) and linewidth, essential information for the further development of high quality photonic-phononic waveguides for SBS applications. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1707.09684v1-abstract-full').style.display = 'none'; document.getElementById('1707.09684v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 30 July, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">7 pages, 5 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1608.08767">arXiv:1608.08767</a> <span> [<a href="https://arxiv.org/pdf/1608.08767">pdf</a>, <a href="https://arxiv.org/format/1608.08767">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1038/s41467-017-00717-y">10.1038/s41467-017-00717-y <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> A chip-integrated coherent photonic-phononic memory </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Merklein%2C+M">Moritz Merklein</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Vu%2C+K">Khu Vu</a>, <a href="/search/physics?searchtype=author&query=Madden%2C+S+J">Stephen J. Madden</a>, <a href="/search/physics?searchtype=author&query=Eggleton%2C+B+J">Benjamin J. Eggleton</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1608.08767v2-abstract-short" style="display: inline;"> Controlling and manipulating quanta of coherent acoustic vibrations - phonons - in integrated circuits has recently drawn a lot of attention, since phonons can function as unique links between radiofrequency and optical signals, allow access to quantum regimes and offer advanced signal processing capabilities. Recent approaches based on optomechanical resonators have achieved impressive quality fa… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1608.08767v2-abstract-full').style.display = 'inline'; document.getElementById('1608.08767v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1608.08767v2-abstract-full" style="display: none;"> Controlling and manipulating quanta of coherent acoustic vibrations - phonons - in integrated circuits has recently drawn a lot of attention, since phonons can function as unique links between radiofrequency and optical signals, allow access to quantum regimes and offer advanced signal processing capabilities. Recent approaches based on optomechanical resonators have achieved impressive quality factors allowing for storage of optical signals. However, so far these techniques have been limited in bandwidth and are incompatible with multi-wavelength operation. In this work, we experimentally demonstrate a coherent buffer in an integrated planar optical waveguide by transferring the optical information coherently to an acoustic hypersound wave. Optical information is extracted using the reverse process. These hypersound phonons have similar wavelengths as the optical photons but travel at 5-orders of magnitude lower velocity. We demonstrate the storage of phase and amplitude of optical information with GHz-bandwidth and show operation at separate wavelengths with negligible cross-talk. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1608.08767v2-abstract-full').style.display = 'none'; document.getElementById('1608.08767v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 27 June, 2017; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 31 August, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2016. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">9 pages, 6 figures, Moritz Merklein and Birgit Stiller contributed equally to this work</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1608.03511">arXiv:1608.03511</a> <span> [<a href="https://arxiv.org/pdf/1608.03511">pdf</a>, <a href="https://arxiv.org/format/1608.03511">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Cryptography and Security">cs.CR</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Emerging Technologies">cs.ET</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Atmospheric and Oceanic Physics">physics.ao-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/OPTICA.4.000611">10.1364/OPTICA.4.000611 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Quantum-limited measurements of optical signals from a geostationary satellite </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=G%C3%BCnthner%2C+K">Kevin G眉nthner</a>, <a href="/search/physics?searchtype=author&query=Khan%2C+I">Imran Khan</a>, <a href="/search/physics?searchtype=author&query=Elser%2C+D">Dominique Elser</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Bayraktar%2C+%C3%96">脰mer Bayraktar</a>, <a href="/search/physics?searchtype=author&query=M%C3%BCller%2C+C+R">Christian R. M眉ller</a>, <a href="/search/physics?searchtype=author&query=Saucke%2C+K">Karen Saucke</a>, <a href="/search/physics?searchtype=author&query=Tr%C3%B6ndle%2C+D">Daniel Tr枚ndle</a>, <a href="/search/physics?searchtype=author&query=Heine%2C+F">Frank Heine</a>, <a href="/search/physics?searchtype=author&query=Seel%2C+S">Stefan Seel</a>, <a href="/search/physics?searchtype=author&query=Greulich%2C+P">Peter Greulich</a>, <a href="/search/physics?searchtype=author&query=Zech%2C+H">Herwig Zech</a>, <a href="/search/physics?searchtype=author&query=G%C3%BCtlich%2C+B">Bj枚rn G眉tlich</a>, <a href="/search/physics?searchtype=author&query=Philipp-May%2C+S">Sabine Philipp-May</a>, <a href="/search/physics?searchtype=author&query=Marquardt%2C+C">Christoph Marquardt</a>, <a href="/search/physics?searchtype=author&query=Leuchs%2C+G">Gerd Leuchs</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1608.03511v2-abstract-short" style="display: inline;"> The measurement of quantum signals that traveled through long distances is of fundamental and technological interest. We present quantum-limited coherent measurements of optical signals, sent from a satellite in geostationary Earth orbit to an optical ground station. We bound the excess noise that the quantum states could have acquired after having propagated 38600 km through Earth's gravitational… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1608.03511v2-abstract-full').style.display = 'inline'; document.getElementById('1608.03511v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1608.03511v2-abstract-full" style="display: none;"> The measurement of quantum signals that traveled through long distances is of fundamental and technological interest. We present quantum-limited coherent measurements of optical signals, sent from a satellite in geostationary Earth orbit to an optical ground station. We bound the excess noise that the quantum states could have acquired after having propagated 38600 km through Earth's gravitational potential as well as its turbulent atmosphere. Our results indicate that quantum communication is feasible in principle in such a scenario, highlighting the possibility of a global quantum key distribution network for secure communication. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1608.03511v2-abstract-full').style.display = 'none'; document.getElementById('1608.03511v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 27 February, 2017; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 11 August, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2016. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">8 pages (4 pages main article, 4 pages supplementary material), 9 figures (4 figures main article, 5 figures supplementary material), Kevin G眉nthner and Imran Khan contributed equally to this work</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Optica 4, 611-616 (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1607.04740">arXiv:1607.04740</a> <span> [<a href="https://arxiv.org/pdf/1607.04740">pdf</a>, <a href="https://arxiv.org/ps/1607.04740">ps</a>, <a href="https://arxiv.org/format/1607.04740">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1367-2630/aa599e">10.1088/1367-2630/aa599e <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Cascaded forward Brillouin scattering to all Stokes orders </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Wolff%2C+C">Christian Wolff</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Eggleton%2C+B+J">Benjamin. J. Eggleton</a>, <a href="/search/physics?searchtype=author&query=Steel%2C+M+J">Michael J. Steel</a>, <a href="/search/physics?searchtype=author&query=Poulton%2C+C+G">Christopher G. Poulton</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1607.04740v2-abstract-short" style="display: inline;"> Inelastic scattering processes such as Brillouin scattering can often function in cascaded regimes and this is likely to occur in certain integrated opto-acoustic devices. We develop a Hamiltonian formalism for cascaded Brillouin scattering valid for both quantum and classical regimes. By regarding Brillouin scattering as the interaction of a single acoustic envelope and a single optical envelope… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1607.04740v2-abstract-full').style.display = 'inline'; document.getElementById('1607.04740v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1607.04740v2-abstract-full" style="display: none;"> Inelastic scattering processes such as Brillouin scattering can often function in cascaded regimes and this is likely to occur in certain integrated opto-acoustic devices. We develop a Hamiltonian formalism for cascaded Brillouin scattering valid for both quantum and classical regimes. By regarding Brillouin scattering as the interaction of a single acoustic envelope and a single optical envelope that covers all Stokes and anti-Stokes orders, we obtain a compact model that is well suited for numerical implementation, extension to include other optical nonlinearities or short pulses, and application in the quantum-optics domain. We then theoretically analyze intra-mode forward Brillouin scattering (FBS) for arbitrary waveguides with and without optical dispersion. In the absence of optical dispersion, we find an exact analytical solution. With a perturbative approach, we furthermore solve the case of weak optical dispersion. Our work leads to several key results on intra-mode FBS. For negligible dispersion, we show that cascaded intra-mode FBS results in a pure phase modulation and discuss how this necessitates specific experimental methods for the observation of fibre-based and integrated FBS. Further, we discuss how the descriptions that have been established in these two classes of waveguides connect to each other and to the broader context of cavity opto-mechanics and Raman scattering. Finally, we draw an unexpected striking similarity between FBS and discrete diffraction phenomena in waveguide arrays, which makes FBS an interesting candidate for future research in quantum-optics. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1607.04740v2-abstract-full').style.display = 'none'; document.getElementById('1607.04740v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 25 August, 2016; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 16 July, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2016. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">18 pages, 8 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1601.07261">arXiv:1601.07261</a> <span> [<a href="https://arxiv.org/pdf/1601.07261">pdf</a>, <a href="https://arxiv.org/format/1601.07261">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/OPTICA.3.000597">10.1364/OPTICA.3.000597 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Efficient single sideband microwave to optical conversion using an electro-optical whispering gallery mode resonator </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Rueda%2C+A">Alfredo Rueda</a>, <a href="/search/physics?searchtype=author&query=Sedlmeir%2C+F">Florian Sedlmeir</a>, <a href="/search/physics?searchtype=author&query=Collodo%2C+M+C">Michele C. Collodo</a>, <a href="/search/physics?searchtype=author&query=Vogl%2C+U">Ulrich Vogl</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Schunk%2C+G">Gerhard Schunk</a>, <a href="/search/physics?searchtype=author&query=Strekalov%2C+D+V">Dmitry V. Strekalov</a>, <a href="/search/physics?searchtype=author&query=Marquardt%2C+C">Christoph Marquardt</a>, <a href="/search/physics?searchtype=author&query=Fink%2C+J+M">Johannes M. Fink</a>, <a href="/search/physics?searchtype=author&query=Painter%2C+O">Oskar Painter</a>, <a href="/search/physics?searchtype=author&query=Leuchs%2C+G">Gerd Leuchs</a>, <a href="/search/physics?searchtype=author&query=Schwefel%2C+H+G+L">Harald G. L. Schwefel</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1601.07261v1-abstract-short" style="display: inline;"> Linking classical microwave electrical circuits to the optical telecommunication band is at the core of modern communication. Future quantum information networks will require coherent microwave-to-optical conversion to link electronic quantum processors and memories via low-loss optical telecommunication networks. Efficient conversion can be achieved with electro-optical modulators operating at th… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1601.07261v1-abstract-full').style.display = 'inline'; document.getElementById('1601.07261v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1601.07261v1-abstract-full" style="display: none;"> Linking classical microwave electrical circuits to the optical telecommunication band is at the core of modern communication. Future quantum information networks will require coherent microwave-to-optical conversion to link electronic quantum processors and memories via low-loss optical telecommunication networks. Efficient conversion can be achieved with electro-optical modulators operating at the single microwave photon level. In the standard electro-optic modulation scheme this is impossible because both, up- and downconverted, sidebands are necessarily present. Here we demonstrate true single sideband up- or downconversion in a triply resonant whispering gallery mode resonator by explicitly addressing modes with asymmetric free spectral range. Compared to previous experiments, we show a three orders of magnitude improvement of the electro-optical conversion efficiency reaching 0.1% photon number conversion for a 10GHz microwave tone at 0.42mW of optical pump power. The presented scheme is fully compatible with existing superconducting 3D circuit quantum electrodynamics technology and can be used for non-classical state conversion and communication. Our conversion bandwidth is larger than 1MHz and not fundamentally limited. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1601.07261v1-abstract-full').style.display = 'none'; document.getElementById('1601.07261v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 26 January, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2016. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">8 pages, 5 figures; comments welcome!</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1510.04507">arXiv:1510.04507</a> <span> [<a href="https://arxiv.org/pdf/1510.04507">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Cryptography and Security">cs.CR</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Emerging Technologies">cs.ET</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Atmospheric and Oceanic Physics">physics.ao-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1109/ICSOS.2015.7425077">10.1109/ICSOS.2015.7425077 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Satellite Quantum Communication via the Alphasat Laser Communication Terminal </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Elser%2C+D">Dominique Elser</a>, <a href="/search/physics?searchtype=author&query=G%C3%BCnthner%2C+K">Kevin G眉nthner</a>, <a href="/search/physics?searchtype=author&query=Khan%2C+I">Imran Khan</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Marquardt%2C+C">Christoph Marquardt</a>, <a href="/search/physics?searchtype=author&query=Leuchs%2C+G">Gerd Leuchs</a>, <a href="/search/physics?searchtype=author&query=Saucke%2C+K">Karen Saucke</a>, <a href="/search/physics?searchtype=author&query=Tr%C3%B6ndle%2C+D">Daniel Tr枚ndle</a>, <a href="/search/physics?searchtype=author&query=Heine%2C+F">Frank Heine</a>, <a href="/search/physics?searchtype=author&query=Seel%2C+S">Stefan Seel</a>, <a href="/search/physics?searchtype=author&query=Greulich%2C+P">Peter Greulich</a>, <a href="/search/physics?searchtype=author&query=Zech%2C+H">Herwig Zech</a>, <a href="/search/physics?searchtype=author&query=G%C3%BCtlich%2C+B">Bj枚rn G眉tlich</a>, <a href="/search/physics?searchtype=author&query=Richter%2C+I">Ines Richter</a>, <a href="/search/physics?searchtype=author&query=Meyer%2C+R">Rolf Meyer</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1510.04507v1-abstract-short" style="display: inline;"> By harnessing quantum effects, we nowadays can use encryption that is in principle proven to withstand any conceivable attack. These fascinating quantum features have been implemented in metropolitan quantum networks around the world. In order to interconnect such networks over long distances, optical satellite communication is the method of choice. Standard telecommunication components allow one… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1510.04507v1-abstract-full').style.display = 'inline'; document.getElementById('1510.04507v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1510.04507v1-abstract-full" style="display: none;"> By harnessing quantum effects, we nowadays can use encryption that is in principle proven to withstand any conceivable attack. These fascinating quantum features have been implemented in metropolitan quantum networks around the world. In order to interconnect such networks over long distances, optical satellite communication is the method of choice. Standard telecommunication components allow one to efficiently implement quantum communication by measuring field quadratures (continuous variables). This opens the possibility to adapt our Laser Communication Terminals (LCTs) to quantum key distribution (QKD). First satellite measurement campaigns are currently validating our approach. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1510.04507v1-abstract-full').style.display = 'none'; document.getElementById('1510.04507v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 15 October, 2015; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2015. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">International Conference on Space Optical Systems and Applications (IEEE ICSOS 2015), October 27 and 28, 2015, New Orleans, USA, 4 pages, 5 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1508.01309">arXiv:1508.01309</a> <span> [<a href="https://arxiv.org/pdf/1508.01309">pdf</a>, <a href="https://arxiv.org/format/1508.01309">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/OE.23.027707">10.1364/OE.23.027707 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Depolarized guided acoustic wave Brillouin scattering in hollow-core photonic crystal fibers </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zhong%2C+W+E+n">Wenjia Elser n茅e Zhong</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Elser%2C+D">Dominique Elser</a>, <a href="/search/physics?searchtype=author&query=Heim%2C+B">Bettina Heim</a>, <a href="/search/physics?searchtype=author&query=Marquardt%2C+C">Christoph Marquardt</a>, <a href="/search/physics?searchtype=author&query=Leuchs%2C+G">Gerd Leuchs</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1508.01309v1-abstract-short" style="display: inline;"> By performing quantum-noise-limited optical heterodyne detection, we observe polarization noise in light after propagation through a hollow-core photonic crystal fiber (PCF). We compare the noise spectrum to the one of a standard fiber and find an increase of noise even though the light is mainly transmitted in air in a hollow-core PCF. Combined with our simulation of the acoustic vibrational mode… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1508.01309v1-abstract-full').style.display = 'inline'; document.getElementById('1508.01309v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1508.01309v1-abstract-full" style="display: none;"> By performing quantum-noise-limited optical heterodyne detection, we observe polarization noise in light after propagation through a hollow-core photonic crystal fiber (PCF). We compare the noise spectrum to the one of a standard fiber and find an increase of noise even though the light is mainly transmitted in air in a hollow-core PCF. Combined with our simulation of the acoustic vibrational modes in the hollow-core PCF, we are offering an explanation for the polarization noise with a variation of guided acoustic wave Brillouin scattering (GAWBS). Here, instead of modulating the strain in the fiber core as in a solid core fiber, the acoustic vibrations in hollow-core PCF influence the effective refractive index by modulating the geometry of the photonic crystal structure. This induces polarization noise in the light guided by the photonic crystal structure. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1508.01309v1-abstract-full').style.display = 'none'; document.getElementById('1508.01309v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 6 August, 2015; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2015. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">8 pages, 5 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Opt. Express 23, 27707 (2015) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1504.00697">arXiv:1504.00697</a> <span> [<a href="https://arxiv.org/pdf/1504.00697">pdf</a>, <a href="https://arxiv.org/format/1504.00697">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/OPTICA.2.000864">10.1364/OPTICA.2.000864 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Classically entangled optical beams for high-speed kinematic sensing </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Berg-Johansen%2C+S">Stefan Berg-Johansen</a>, <a href="/search/physics?searchtype=author&query=T%C3%B6ppel%2C+F">Falk T枚ppel</a>, <a href="/search/physics?searchtype=author&query=Stiller%2C+B">Birgit Stiller</a>, <a href="/search/physics?searchtype=author&query=Banzer%2C+P">Peter Banzer</a>, <a href="/search/physics?searchtype=author&query=Ornigotti%2C+M">Marco Ornigotti</a>, <a href="/search/physics?searchtype=author&query=Giacobino%2C+E">Elisabeth Giacobino</a>, <a href="/search/physics?searchtype=author&query=Leuchs%2C+G">Gerd Leuchs</a>, <a href="/search/physics?searchtype=author&query=Aiello%2C+A">Andrea Aiello</a>, <a href="/search/physics?searchtype=author&query=Marquardt%2C+C">Christoph Marquardt</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1504.00697v2-abstract-short" style="display: inline;"> Tracking the kinematics of fast-moving objects is an important diagnostic tool for science and engineering. Existing optical methods include high-speed CCD/CMOS imaging, streak cameras, lidar, serial time-encoded imaging and sequentially timed all-optical mapping. Here, we demonstrate an entirely new approach to positional and directional sensing based on the concept of classical entanglement in v… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1504.00697v2-abstract-full').style.display = 'inline'; document.getElementById('1504.00697v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1504.00697v2-abstract-full" style="display: none;"> Tracking the kinematics of fast-moving objects is an important diagnostic tool for science and engineering. Existing optical methods include high-speed CCD/CMOS imaging, streak cameras, lidar, serial time-encoded imaging and sequentially timed all-optical mapping. Here, we demonstrate an entirely new approach to positional and directional sensing based on the concept of classical entanglement in vector beams of light. The measurement principle relies on the intrinsic correlations existing in such beams between transverse spatial modes and polarization. The latter can be determined from intensity measurements with only a few fast photodiodes, greatly outperforming the bandwidth of current CCD/CMOS devices. In this way, our setup enables two-dimensional real-time sensing with temporal resolution in the GHz range. We expect the concept to open up new directions in photonics-based metrology and sensing. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1504.00697v2-abstract-full').style.display = 'none'; document.getElementById('1504.00697v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 15 January, 2016; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 2 April, 2015; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2015. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">v2 includes the real-time measurement from the published version. Reference [29] added. Minor experimental details added on page 6</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Optica 2(10), 864-868 (2015) </p> </li> </ol> <div class="is-hidden-tablet">  <span class="help" style="display: inline-block;"><a href="https://github.com/arXiv/arxiv-search/releases">Search v0.5.6 released 2020-02-24</a>  </span> </div> </div> </main> <footer> <div class="columns is-desktop" role="navigation" aria-label="Secondary">  <div class="column"> <div class="columns"> <div class="column"> <ul class="nav-spaced"> <li><a href="https://info.arxiv.org/about">About</a></li> <li><a href="https://info.arxiv.org/help">Help</a></li> </ul> </div> <div class="column"> <ul class="nav-spaced"> <li> <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512" class="icon filter-black" role="presentation"><title>contact arXiv</title><desc>Click here to contact arXiv</desc><path d="M502.3 190.8c3.9-3.1 9.7-.2 9.7 4.7V400c0 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