Generalized approach to quantify correlations in bipartite quantum systems

D. G. Bussandri, A. P. Majtey, P. W. Lamberti, T. M. Osán

Published 2018-05-29Version 1

In this work we developed a general approach to the problem of detecting and quantifying different kind of correlations in bipartite quantum systems. Our method is based on the use of distances between quantum states and processes. We rely upon the premise that total correlations can be separated into classical and quantum contributions due to their different nature. In addition, according to recently discussed criteria, we determined the requirements to be satisfied by distances in order to generate correlation measures physically well behaved. The proposed measures allow us to quantify quantum, classical and total correlations. As a consequence of our analysis we were able to proof that the resulting quantum correlations measures are monotonically non-increasing under any local commutative preserving operations. It is important to remark that this last result for quantum discord, which is included in our proposed measures, was until now an open question.