Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)

Quantum Memory in Brillouin-Active Waveguides

Changlong Zhu, Birgit Stiller

Published Jun 23, 2025• 0 citations
Publisher

Abstract

Storage and retrieval of optical quantum states are key elements for the realization of quantum communication and quantum networks. Here, we propose to realize a memory for light states in Brillouin-active waveguides. It is achieved by transferring quantum states between optical photons and acoustic phonons via Brillouin anti-Stokes scattering. By controlling the optoacoustic interaction with pulsed pumps, we demonstrate that it is possible to write, store, and read out of optical quantum states with high fidelity in state-of-the-art Brillouin-active waveguides.

DOI
10.1109/cleo/europe-eqec65582.2025.11111338

Related papers

A solid-state quantum memory based on a continuous optoacoustic system

Changlong Zhu, Claudiu Genes, Birgit Stiller

Quantum memories for optical states are essential resources for quantum communication and information processing. We propose a quantum memory protocol based on coherent photon-phonon transduction in a Brillouin-active optical waveguide supporting traveling acoustic modes. A pulsed pump drives an effective beam-splitter interaction between optical and acoustic fields, enabling the mapping of a propagating optical quantum state onto a traveling phononic excitation and its subsequent retrieval on demand. Using a continuum optoacoustic model, we show that the protocol enables broadband quantum state storage in a distributed medium without relying on discrete cavity modes. Analytical and numerical results demonstrate high-fidelity storage and retrieval of squeezed and entangled states under experimentally realistic parameters. The memory bandwidth is set by the Brillouin interaction and can reach hundreds of MHz. Our results identify continuum Brillouin optomechanical systems as a scalable platform for broadband quantum memories and multimode quantum signal processing.

quant-pharXiv:2604.05602•Apr 8, 2026•0 citations

Optoacoustic Entanglement in a Continuous Brillouin-Active Solid State System

Changlong Zhu, Claudiu Genes, Birgit Stiller

Entanglement in hybrid quantum systems comprised of fundamentally different degrees of freedom, such as light and mechanics, is of interest for a wide range of applications in quantum technologies. Here, we propose to engineer bipartite entanglement between traveling acoustic phonons in a Brillouin active solid state system and the accompanying light wave. The effect is achieved by applying optical pump pulses to state-of-the-art waveguides, exciting a Brillouin Stokes process. This pulsed approach, in a system operating in a regime orthogonal to standard optomechanical setups, allows for the generation of entangled photon-phonon pairs, resilient to thermal fluctuations. We propose an experimental platform where readout of the optoacoustics entanglement is done by the simultaneous detection of Stokes and anti-Stokes photons in a two-pump configuration. The proposed mechanism presents an important feature in that it does not require initial preparation of the quantum ground state of the phonon mode.

arXiv:2401.10665•Physical Review Letters•Nov 13, 2024•12 citations

High-Speed Coherent Photonic Random-Access Memory in Long-Lasting Sound Waves

Andreas Geilen, Steven Becker, Birgit Stiller

High Resolution Image Download MS PowerPoint Slide 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. Such an optoacoustic memory has shown great potential as it fulfills 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 1 order of magnitude and coherently retrieve optical information after a storage time of 123 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 6. We demonstrate the capability of our scheme by measuring the initial and readout optical data pulses 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 4.2–20 K and compare the findings to continuous wave measurements. The extended storage time is beneficial not only 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.

arXiv:2311.06219•ACS Photonics•Oct 18, 2024•9 citations

Optoacoustic entanglement in Brillouin-active waveguides

Changlong Zhu, Claudiu Genes, Birgit Stiller

Entanglement is a key resource to many emerging quantum technologies. Here, we present a scheme to engineer bipartite entanglement between traveling acoustic phonons and photons in Brillouin-active waveguides at a modest high environment temperature.

Quantum 2.0 Conference and Exhibition•Jan 1, 2024•0 citations

Memory Device for Photons by exploiting Brillouin Interactions in Nanowires

Hashem Zoubi

Memory devices for single photons are notable components for quantum information processing and quantum communications. The present study investigates the possibility of achieving storage of light at the level of single photons inside nanofibers by exploiting stimulated Brillouin scattering. We present first the standard approach using a coherent buffer in a nanoscale waveguide by transferring the optical signal coherently to an acoustic wave, and that can be extracted by the reverse process. The life time of the acoustic wave put limitation on the applicability of such approach for single photon signals. We introduce a configuration for achieving a slow signal at the level of single photons without gain or loss. The process utilizes photon-phonon Brillouin interactions involving two counter propagating pump fields. The photon storage is achieved through time delay of significantly slow signal inside nanowires. We address the condition for getting negligible influence due to the scattering off thermal phonons.

quant-pharXiv:2607.01816•Physical Review A•Jul 3, 2026•0 citations

Quantum Coherent Control in Pulsed Waveguide Optomechanics for Photon-Phonon Entanglement via Brillouin Scattering

Changlong Zhu, Junyin Zhang, Christian Wolff +1 more

Brillouin optomechanics provides a way to coherently control traveling acoustic excitations in waveguides system, which enables the manipulation and processing of classical and quantum information. Although Brillouin optomechanics has been largely investigated in the steady-state regime using continuous waves [1]–[3], waveguide experiments are often realized by using optical pulses for example for Brillouin-based memory [4], [5]. This requires a dynamic framework treatment for the temporal domain including the noise dynamics.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 26, 2023•0 citations
Storage and retrieval of optical quantum states are key elements for the realization of quantum communication and quantum networks. Here, we propose to realize a memory for light states in Brillouin-active waveguides. It is achieved by transferring quantum states between optical photons and acoustic phonons via Brillouin anti-Stokes scattering. By controlling the optoacoustic interaction with pulsed pumps, we demonstrate that it is possible to write, store, and read out of optical quantum states with high fidelity in state-of-the-art Brillouin-active waveguides.
Quantum memories for optical states are essential resources for quantum communication and information processing. We propose a quantum memory protocol based on coherent photon-phonon transduction in a Brillouin-active optical waveguide supporting traveling acoustic modes. A pulsed pump drives an effective beam-splitter interaction between optical and acoustic fields, enabling the mapping of a propagating optical quantum state onto a traveling phononic excitation and its subsequent retrieval on demand. Using a continuum optoacoustic model, we show that the protocol enables broadband quantum state storage in a distributed medium without relying on discrete cavity modes. Analytical and numerical results demonstrate high-fidelity storage and retrieval of squeezed and entangled states under experimentally realistic parameters. The memory bandwidth is set by the Brillouin interaction and can reach hundreds of MHz. Our results identify continuum Brillouin optomechanical systems as a scalable platform for broadband quantum memories and multimode quantum signal processing.
Entanglement in hybrid quantum systems comprised of fundamentally different degrees of freedom, such as light and mechanics, is of interest for a wide range of applications in quantum technologies. Here, we propose to engineer bipartite entanglement between traveling acoustic phonons in a Brillouin active solid state system and the accompanying light wave. The effect is achieved by applying optical pump pulses to state-of-the-art waveguides, exciting a Brillouin Stokes process. This pulsed approach, in a system operating in a regime orthogonal to standard optomechanical setups, allows for the generation of entangled photon-phonon pairs, resilient to thermal fluctuations. We propose an experimental platform where readout of the optoacoustics entanglement is done by the simultaneous detection of Stokes and anti-Stokes photons in a two-pump configuration. The proposed mechanism presents an important feature in that it does not require initial preparation of the quantum ground state of the phonon mode.
High Resolution Image Download MS PowerPoint Slide 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. Such an optoacoustic memory has shown great potential as it fulfills 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 1 order of magnitude and coherently retrieve optical information after a storage time of 123 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 6. We demonstrate the capability of our scheme by measuring the initial and readout optical data pulses 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 4.2–20 K and compare the findings to continuous wave measurements. The extended storage time is beneficial not only 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.
Memory devices for single photons are notable components for quantum information processing and quantum communications. The present study investigates the possibility of achieving storage of light at the level of single photons inside nanofibers by exploiting stimulated Brillouin scattering. We present first the standard approach using a coherent buffer in a nanoscale waveguide by transferring the optical signal coherently to an acoustic wave, and that can be extracted by the reverse process. The life time of the acoustic wave put limitation on the applicability of such approach for single photon signals. We introduce a configuration for achieving a slow signal at the level of single photons without gain or loss. The process utilizes photon-phonon Brillouin interactions involving two counter propagating pump fields. The photon storage is achieved through time delay of significantly slow signal inside nanowires. We address the condition for getting negligible influence due to the scattering off thermal phonons.
Brillouin optomechanics provides a way to coherently control traveling acoustic excitations in waveguides system, which enables the manipulation and processing of classical and quantum information. Although Brillouin optomechanics has been largely investigated in the steady-state regime using continuous waves [1]–[3], waveguide experiments are often realized by using optical pulses for example for Brillouin-based memory [4], [5]. This requires a dynamic framework treatment for the temporal domain including the noise dynamics.