Experimental Investigation of the Evolution of Gaussian Quantum Discord in an Open System

TL;DR

This paper experimentally studies how Gaussian quantum discord, a measure of quantum correlations, evolves under noise and dissipation, revealing conditions for its degradation and revival in open quantum systems.

Contribution

It provides the first experimental analysis of Gaussian discord dynamics under noise and dissipation, including discord death and revival phenomena.

Findings

Noise degrades Gaussian discord

Dissipation can increase Gaussian discord for some states

Discord can be revived after near-death through dissipation

Abstract

Gaussian quantum discord is a measure of quantum correlations in Gaussian systems. Using Gaussian discord we quantify the quantum correlations of a bipartite entangled state and a separable two-mode mixture of coherent states. We experimentally analyze the effect of noise addition and dissipation on Gaussian discord and show that the former noise degrades the discord while the latter noise for some states leads to an increase of the discord. In particular, we experimentally demonstrate the near-death of discord by noisy evolution and its revival through dissipation.