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arXiv · 2007.05826

Squeezing and multimode entanglement of surface acoustic wave phonons

Gustav Andersson·Shan W. Jolin·Marco Scigliuzzo·Riccardo Borgani·Mats O. Tholén·J. C. Rivera Hernández·Vitaly Shumeiko·David B. Haviland·Per Delsing
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Abstract

Exploiting multiple modes in a quantum acoustic device could enable applications in quantum information in a hardware-efficient setup, including quantum simulation in a synthetic dimension and continuous-variable quantum computing with cluster states.We develop a multimode surface acoustic wave (SAW) resonator with a superconducting quantum interference device (SQUID) integrated in one of the Bragg reflectors. The interaction with the SQUID-shunted mirror gives rise to coupling between the more than 20 accessible resonator modes. We exploit this coupling to demonstrate two-mode squeezing of SAW phonons, as well as four-mode multipartite entanglement. Our results open avenues for continuous-variable quantum computing in a compact hybrid quantum system.

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Gustav Andersson, Shan W. Jolin, Marco Scigliuzzo, Riccardo Borgani, Mats O. Tholén, J. C. Rivera Hernández, Vitaly Shumeiko, David B. Haviland, Per Delsing. 2020-07-11. Squeezing and multimode entanglement of surface acoustic wave phonons. https://doi.org/10.1103/prxquantum.3.010312

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