arXiv:2305.15741 · Physical Review A
Coherence filtration under strictly incoherent operations
C. L. Liu, Chuan Sun
Abstract
We study the task of coherence filtration under strictly incoherent operations. The aim of this task is to transform a given state $\ensuremath{\rho}$ into another one ${\ensuremath{\rho}}^{\ensuremath{'}}$ whose fidelity with the maximally coherent state is maximal by using stochastic strictly incoherent operations. We find that the maximal fidelity between ${\ensuremath{\rho}}^{\ensuremath{'}}$ and the maximally coherent state is given by a multiple of the $\mathrm{\ensuremath{\Delta}}$ robustness of coherence, $R(\ensuremath{\rho}\ensuremath{\parallel}\mathrm{\ensuremath{\Delta}}\ensuremath{\rho}):=min{\ensuremath{\lambda}|\ensuremath{\rho}\ensuremath{\le}\ensuremath{\lambda}\mathrm{\ensuremath{\Delta}}\ensuremath{\rho}}$, which provides $R(\ensuremath{\rho}\ensuremath{\parallel}\mathrm{\ensuremath{\Delta}}\ensuremath{\rho})$ an operational interpretation. Finally, we provide a coherence measure based on the task of coherence filtration.