Dynamics of quantum discord in asymmetric and local non-Markovian environments

TL;DR

This paper analyzes how quantum and classical correlations decay in asymmetric, non-Markovian environments, revealing sudden changes in decay rates and ways to prolong quantum correlations through environmental memory effects.

Contribution

It provides an analytical study of non-Markovian decoherence of correlations in asymmetric environments, highlighting the dynamics and preservation of quantum discord.

Findings

Quantum and classical correlations decay synchronously for certain states.

Decay rates of correlations change suddenly at a characteristic time.

Environmental memory effects can prolong quantum correlations.

Abstract

The non-Markovian decoherence of quantum and classical correlations is analytically obtained when two qubits are asymmetrically subjected to the bit flip channel and phase flip channel. For one class of initial mixed states, quantum correlations quantified by quantum discord decay synchronously with classical correlations. The discovery that the decaying rates of quantum and classical correlations suddenly change at the characteristic time is physically interpreted by the distance from quantum state to the closest classical states. In a large time interval, quantum correlations are greater than classical correlations. The quantum and classical correlations can be preserved over a longer period of time via the kernel characterizing the environment memory effects.