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arXiv · 2204.10498

Detecting quantumness in uniform precessions

Lin Htoo Zaw·Clive Cenxin Aw·Zakarya Lasmar·Valerio Scarani
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Abstract

Building on work by Tsirelson, we present a family of protocols that detect the nonclassicality of suitable states of a single quantum system, under the sole assumption that the measured dynamical observable undergoes a uniform precession. The case of the harmonic oscillator was anticipated in the work by Tsirelson, which we extend. We then apply the protocols to finite-dimensional spins that undergo uniform precession in real space and find a gap between the classical and the quantum expectations for every $j\geq \frac{3}{2}$ (excluding $j=2$).

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Lin Htoo Zaw, Clive Cenxin Aw, Zakarya Lasmar, Valerio Scarani. 2022-09-26. Detecting quantumness in uniform precessions. https://doi.org/10.1103/physreva.106.032222

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