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arXiv · 2104.03844

Fidelity based purity and coherence for quantum states

Indrajith V S·R. Muthuganesan·R. Sankaranarayanan
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Abstract

Purity and coherence of a quantum state are recognized as useful resources for various information processing tasks. In this article, we propose a fidelity based valid measure of purity and coherence monotone and establish a relationship between them. This formulation of coherence is extended to quantum correlation relative to measurement. We have also studied the role of weak measurement on purity.

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Indrajith V S, R. Muthuganesan, R. Sankaranarayanan. 2021-04-08. Fidelity based purity and coherence for quantum states. https://arxiv.org/abs/2104.03844

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