Quantum discord and its geometric measure with death entanglement in correlated dephasing two qubits system

TL;DR

This paper investigates how quantum discord, its geometric measure, and classical correlations evolve in a bipartite quantum system under dephasing, highlighting the role of initial state purity in correlation dynamics.

Contribution

It introduces the impact of initial state purity on quantum and classical correlation dynamics in a dephasing model, identifying regions with no quantum correlations.

Findings

Quantum correlations decay instantaneously under dephasing.

Classical correlations increase as quantum correlations decay.

Initial state purity determines the presence or absence of quantum correlations.

Abstract

The quantum correlations, including entanglement and discord with its geometric measure, and classical correlation are studied for a bipartite partition of a open or closed quantum system. It is found that the purity of the initial state plays an important role in the dynamics of quantum and classical correlations. In the dephasing model, the quantum correlations loss and the classical correlation gain are instantaneously happen. While, the purity of the initial state destroys the quantum correlations which is resulted by the unitary interaction. Therefore, with the purity parameter, a particular region in which there is no state have quantum correlations can be determined.