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arXiv · 2305.15741

Coherence filtration under strictly incoherent operations

C. L. Liu·C. P. Sun
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Abstract

We study the task of coherence filtration under strictly incoherent operations in this paper. The aim of this task is to transform a given state $\rho$ into another one $\rho^\prime$ whose fidelity with the maximally coherent state is maximal by using stochastic strictly incoherent operations. We find that the maximal fidelity between $\rho^\prime$ and the maximally coherent state is given by a multiple of the $\Delta$ robustness of coherence $R(\rho\|\Delta\rho):=\min\{\uplambda|\rho\leq\uplambda\Delta\rho\}$, which provides $R(\rho\|\Delta\rho)$ an operational interpretation. Finally, we provide a coherence measure based on the task of coherence filtration.

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C. L. Liu, C. P. Sun. 2023-05-25. Coherence filtration under strictly incoherent operations. https://doi.org/10.1103/physreva.107.052424

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