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arXiv · 2311.12547

Quantifying the imaginarity of quantum states via Tsallis relative entropy

Jianwei Xu
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Abstract

It is a fundamental question that why quantum mechanics uses complex numbers instead of only real numbers. To address this topic, recently, a rigorous resource theory for the imaginarity of quantum states were established, and several imaginarity measures were proposed. In this work, we propose a new imaginarity measure based on the Tsallis relative entropy. This imaginarity measure has explicit expression, and also, it is computable for bosonic Gaussian states.

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Jianwei Xu. 2023-11-21. Quantifying the imaginarity of quantum states via Tsallis relative entropy. https://doi.org/10.1016/j.physleta.2024.130024

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