Generation and protection of steady-state quantum correlations due to quantum channels with memory

TL;DR

This paper investigates how quantum channels with memory can generate and preserve steady-state quantum correlations, such as entanglement and discord, in two-qubit systems affected by various noise types.

Contribution

It introduces a scheme for generating and protecting steady-state quantum correlations using correlated quantum channels with memory, analyzing different noise models.

Findings

Steady-state entanglement can be generated without initial entanglement.

Quantum discord persists longer than entanglement, especially with channel memory.

Quantum correlations can be maintained at long times as channel memory approaches maximum.

Abstract

We have proposed a scheme of the generation and preservation of two-qubit steady state quantum correlations through quantum channels where successive uses of the channels are correlated. Different types of noisy channels with memory, such as amplitude damping, phase-damping, and depolarizing channels have been taken into account. Some analytical or numerical results are presented. The effect of channels with memory on dynamics of quantum correlations has been discussed in detail. The results show that, steady state entanglement between two independent qubits without entanglement subject to amplitude damping channel with memory can be generated. Besides, we compare the dynamics of entanglement with that of quantum discord when a two-qubit system is prepared in an entangled state. We show that entanglement dynamics suddenly disappears, while quantum discord displays only in the asymptotic limit. Two-qubit quantum correlations can be preserved at a long time in the limit of $\mu\rightarrow1$.