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arXiv · 2209.05197

Salient signatures of entanglement in the surrounding environment

Łukasz Rudnicki·Waldemar Kłobus·Otavio A. D. Molitor·Wiesław Laskowski
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Abstract

We develop a model in which presence of entanglement in a quantum system can be confirmed through coarse observations of the environment surrounding the system. This counter-intuitive effect becomes possible when interaction between the system and its environment is proportional to an observable being an entanglement witness. While presenting intuitive examples we show that: i) a cloud of an ideal gas, when subject to a linear potential coupled with the entanglement witness, accelerates in the direction dictated by the sign of the witness; ii) when the environment is a radiation field, the direction of dielectric polarization depends on the presence of entanglement; iii) quadratures of electromagnetic field in a cavity coupled with two qubits (or a four-level atom) are displaced in the same manner.

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Łukasz Rudnicki, Waldemar Kłobus, Otavio A. D. Molitor, Wiesław Laskowski. 2022-09-12. Salient signatures of entanglement in the surrounding environment. https://arxiv.org/abs/2209.05197

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