Quantifying the phase of quantum states

Jianwei Xu

doi:10.1016/j.physleta.2023.129049

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arXiv · 2304.09028

Quantifying the phase of quantum states

Jianwei Xu

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Abstract

Phase is a basic ingredient for quantum states since quantum mechanics uses complex numbers to describe quantum states. In this letter, we introduce a rigorous framework to quantify the phase of quantum states. To do so, we regard phase as a quantum resource, and specify the free states and free operations. We determine the conditions a phase measure should satisfy and provide some phase measures. We also propose the notion of intrinsic phase for quantum states.

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Jianwei Xu. 2023-04-18. Quantifying the phase of quantum states. https://doi.org/10.1016/j.physleta.2023.129049

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