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arXiv · 2007.09587

Coherence measures with respect to general quantum measurements

Jianwei Xu·Lian-He Shao·Shao-Ming Fei
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Abstract

Quantum coherence with respect to orthonormal bases has been studied extensively in the past few years. Recently, Bischof, et al. [Phys. Rev. Lett. 123, 110402 (2019)] generalized it to the case of general positive operator-valued measure (POVM) measurements. Such POVM-based coherence, including the block coherence as a special case, have significant operational interpretations in quantifying the advantage of quantum states in quantum information processing. In this work we first establish an alternative framework for quantifying the block coherence and provide several block coherence measures. We then present several coherence measures with respect to POVM measurements, and prove a conjecture on the $l_{1}$-norm related POVM coherence measure.

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Jianwei Xu, Lian-He Shao, Shao-Ming Fei. 2020-07-19. Coherence measures with respect to general quantum measurements. https://doi.org/10.1103/physreva.102.012411

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