Frozen discord in stochastic dephasing environment

TL;DR

This paper studies how quantum discord can remain unchanged over time in qubits affected by stochastic dephasing, highlighting the role of information backflow from the environment.

Contribution

It demonstrates the conditions under which quantum discord remains frozen in a stochastic dephasing environment and links this phenomenon to non-Markovian information backflow.

Findings

Quantum discord can be frozen for a finite time in stochastic dephasing environments.

The preservation of discord is related to non-Markovian information backflow.

Comparison with quantum dephasing environments shows similar behavior.

Abstract

Preserving quantum coherence is fundamental challenge in the field of quantum computation. Here, I investigate the frozen discord phenomenon and non-Markovianity for qubits experiencing local dephasing in a classical environment. The quantum discord of a certain initial bipartite state, independently interacting with stochastic Gaussian fields, can be frozen for a finite time. The preservation of discord is shown to be intimately related to the backflow of information from the environment. The relevant result for quantum dephasing environment is compared.