Spontaneous emission can locally create quantum discord out of classical correlations

TL;DR

This paper demonstrates that spontaneous emission in independent two-level atoms can generate transient quantum discord from initially classically correlated states, revealing local creation of quantum correlations in a simple physical system.

Contribution

It shows that local spontaneous emission can induce quantum discord from classical correlations in non-interacting atoms, a novel insight into quantum correlation dynamics.

Findings

Classically correlated states evolve into states with quantum discord due to spontaneous emission.

Quantum discord can be transiently generated in non-interacting atomic systems.

Local environmental interactions can create quantum correlations without direct atom-atom interaction.

Abstract

We consider local time evolution given by spontaneous emission in the system of independent two-level atoms. It is shown that all classically correlated initial states are driven into the states with transient non-zero quantum discord. Thus local creation of genuine quantum correlations can be observed in a simple physical system of non-interacting atoms which are not completely isolated from the environment.