Quantum Coherence Bounds the Distributed Discords
Zhi-Xiang Jin, Xianqing Li-Jost, Shao-Ming Fei, and Cong-Feng Qiao
Contact the author: Please use for correspondence this email.
Submission date: 12. Sep. 2020
Download full preprint: PDF (519 kB)
Establishing quantum correlations between two remote parties by sending an information carrier is an essential step of many protocols in quantum information processing. We obtain trade-off relations between discords and coherence within a bipartite system. Then we study the distribution of coherence in a bipartite quantum state by using the relations of relative entropy and mutual information. We show that the increase of the relative entropy of discord between two remote parties is bounded by the nonclassical correlations quantified by the relative entropy of coherence between the carrier and two remote parties, providing an optimal protocol for discord distribution and showing that quantum correlations are the essential resource for such tasks.