Basis-independent quantum coherence and its distribution
Abstract
We analyze a basis-independent definition of quantum coherence. The maximally mixed state is used as the reference state, which allows for a way of defining coherence that is invariant under arbitrary unitary transformations. The basis-independent approach is applied to finding the distri- bution of the coherence within a multipartite system, where the contributions due to correlations between the subsystems and within each subsystem are isolated. The use of the square root of the Jensen-Shannon divergence allows for inequality relations to be derived between these quantities, giving a geometrical picture within the Hilbert space of the system. We describe the relationship between the basis-independent and the basis-dependent approaches, and argue that many advan- tages exist for the former method. The formalism is illustrated with several numerical examples which show that the states can be characterized in a simple and effective manner.
Cite
@article{arxiv.1805.09263,
title = {Basis-independent quantum coherence and its distribution},
author = {Chandrashekar Radhakrishnan and Zhe Ding and Fazhan Shi and Jiangfeng Du and Tim Byrnes},
journal= {arXiv preprint arXiv:1805.09263},
year = {2019}
}