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arXiv · 2209.06635

Macroscopic quantum test with bulk acoustic wave resonators

Björn Schrinski·Yu Yang·Uwe von Lüpke·Marius Bild·Yiwen Chu·Klaus Hornberger·Stefan Nimmrichter·Matteo Fadel
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Abstract

Recently, solid-state mechanical resonators have become a platform for demonstrating non-classical behavior of systems involving a truly macroscopic number of particles. Here, we perform the most macroscopic quantum test in a mechanical resonator to date, which probes the validity of quantum mechanics at the microgram mass scale. This is done by a direct measurement of the Wigner function of a high-overtone bulk acoustic wave resonator mode, monitoring the gradual decay of negativities over tens of microseconds. While the obtained macroscopicity of $μ= 11.3$ is on par with state-of-the-art atom interferometers, future improvements of mode geometry and coherence times could confirm the quantum superposition principle at unprecedented scales.

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Björn Schrinski, Yu Yang, Uwe von Lüpke, Marius Bild, Yiwen Chu, Klaus Hornberger, Stefan Nimmrichter, Matteo Fadel. 2023-02-16. Macroscopic quantum test with bulk acoustic wave resonators. https://doi.org/10.1103/physrevlett.130.133604

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