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arXiv · 2305.06705

Bounds on positive operator-valued measure based coherence of superposition

Meng-Li Guo·Jin-Min Liang·Bo Li·Shao-Ming Fei·Zhi-Xi Wang
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Abstract

Quantum coherence is a fundamental feature of quantum physics and plays a significant role in quantum information processing. By generalizing the resource theory of coherence from von Neumann measurements to positive operator-valued measures (POVMs), POVM-based coherence measures have been proposed with respect to the relative entropy of coherence, the $l_1$ norm of coherence, the robustness of coherence and the Tsallis relative entropy of coherence. We derive analytically the lower and upper bounds on these POVM-based coherence of an arbitrary given superposed pure state in terms of the POVM-based coherence of the states in superposition. Our results can be used to estimate range of quantum coherence of superposed states. Detailed examples are presented to verify our analytical bounds.

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Meng-Li Guo, Jin-Min Liang, Bo Li, Shao-Ming Fei, Zhi-Xi Wang. 2023-05-11. Bounds on positive operator-valued measure based coherence of superposition. https://doi.org/10.1088/1674-1056%2Facb9f1

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