Quantum coherence and correlations in quantum system

TL;DR

This paper explores the relationships between quantum coherence, entanglement, discord, and quantum deficit, providing new insights into their interconnections and proposing an uncertainty-like relation involving coherence and entropy.

Contribution

It introduces an uncertainty-like expression linking coherence and entropy, and clarifies the relation between quantum deficit, discord, and coherence in bipartite systems.

Findings

Quantum deficit equals the sum of quantum discord and relative entropy of coherence.

The paper establishes a relation between coherence and entropy in quantum systems.

It discusses the interplay between coherence, entanglement, and discord.

Abstract

Criteria of measure quantifying quantum coherence, a unique property of quantum system, are proposed recently. In this paper, we first give an uncertainty-like expression relating the coherence and the entropy of quantum system. This finding allows us to discuss the relations between the entanglement and the coherence. Further, we discuss in detail the relations among the coherence, the discord and the deficit in the bipartite quantum system. We show that, the one-way quantum deficit is equal to the sum between quantum discord and the relative entropy of coherence of measured subsystem.