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arXiv · 2401.10665

Optoacoustic entanglement in a continuous Brillouin-active solid state system

Changlong Zhu·Claudiu Genes·Birgit Stiller
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Abstract

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.

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Changlong Zhu, Claudiu Genes, Birgit Stiller. 2024-01-19. Optoacoustic entanglement in a continuous Brillouin-active solid state system. https://arxiv.org/abs/2401.10665

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