Protecting quantum correlations of two qubits in independent non-Markovian environments by bang-bang pulses

TL;DR

This paper explores how bang-bang pulses can protect quantum correlations between two qubits in non-Markovian environments, showing that pulse application can enhance and sustain quantum discord more effectively.

Contribution

It demonstrates that applying bang-bang pulses can improve and protect quantum correlations in two qubits interacting with non-Markovian environments, highlighting the importance of pulse timing.

Findings

Quantum discord exhibits sudden change phenomena.

Shorter pulse intervals enhance protection of quantum correlations.

Longer reservoir correlation times improve correlation preservation.

Abstract

We investigate how to protect quantum correlations for two qubits each locally interacting with its own non-Markovian environment by making use of bang-bang pulses. It is shown that the quantum discord dynamics presents the phenomenon of sudden change for some certain initial states. We also find that the amount of quantum correlation between two qubits can be improved by applying a train of pulses and protected more effectively with shorter interval pulses or longer reservoir correlation time.