# Accessible Coherence and Coherence Distribution

## TL;DR

This paper introduces the concept of accessible coherence in bipartite quantum systems, analyzing how coherence can be distributed and accessed through local measurements and classical communication.

## Contribution

It defines accessible coherence, derives formulas for local accessible and remaining coherence, and explores their distribution in bipartite systems for different coherence measures.

## Key findings

- Accessible coherence can exceed local coherence via measurements and communication.
- Formulas for accessible and remaining coherence are derived.
- Distribution patterns of coherence are illustrated with examples.

## Abstract

The definition of accessible coherence is proposed. Through local measurement on the other subsystem and one way classical communication, a subsystem can access more coherence than the coherence of its density matrix. Based on the local accessible coherence, the part that can not be locally accessed is also studied, which we call it remaining coherence. We study how the bipartite coherence is distributed by partition for both l1 norm coherence and relative entropy coherence, and the expressions for local accessible coherence and remaining coherence are derived. we also study some examples to illustrate the distribution.