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arXiv · 2304.07154

Exclusion principle for nonlocal advantage of quantum coherence

Priya Ghosh·Mahasweta Pandit·Chirag Srivastava·Ujjwal Sen
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Abstract

Coherences in mutually unbiased bases of states of an isolated quantum system follow a complementarity relation. The nonlocal advantage of quantum coherence (NAQC), defined in a bipartite scenario, is a situation in which the average quantum coherences of the ensembles of one subsystem, effected by a measurement performed on the other subsystem, violates the complementarity relation. We analyze two criteria to detect NAQC for bipartite quantum states. We construct a more generalized version of the criterion to detect NAQC that is better than the standard criterion as it can capture more states exhibiting NAQC. We prove the local unitary invariance of these NAQC criteria. Further on, we focus on investigating the monogamy properties of NAQC in the tripartite scenario. We check for monogamy of NAQC from two perspectives, differentiated by whether or not the nodal observer in the monogamy relation performs the measurement for the nonlocal advantage. We find in particular that in the case where the nodal observer does not perform the measurement, a strong monogamy relation - an exclusion principle - is exhibited by NAQC.

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Priya Ghosh, Mahasweta Pandit, Chirag Srivastava, Ujjwal Sen. 2023-04-14. Exclusion principle for nonlocal advantage of quantum coherence. https://doi.org/10.1103/physreva.108.022410

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