Dressed-state master equation for two strongly coupled two-level atoms with long-lived entanglement

TL;DR

This paper develops a dressed-state master equation for two strongly coupled two-level atoms, revealing how their entanglement evolves over different time scales and providing a compact method to analyze their decay dynamics.

Contribution

It introduces a dressed-state master equation in Lindblad form for strongly coupled atoms, enabling simplified analysis of their entanglement dynamics and decay processes.

Findings

Transient maximally entangled state forms on short time scale

Two distinct decay time scales are identified

Entanglement gradually decays to steady state

Abstract

We derive a dressed-state master equation in Lindblad form for two strongly coupled two-level atoms. The resulting decay dynamics are governed by Lindblad operators that couple different dressed states. We show that the eigenvalues and eigenvectors of the Liouvillian can be obtained in a compact form, since each off-diagonal element in the dressed-state basis constitutes an eigenvector. Depending on the interatomic distance and the atomic transition frequency, two distinct time scales emerge. On a short time scale, the system relaxes toward two states, one of which corresponds to a transient, maximally entangled configuration. On a longer time scale, this entangled state gradually decays to the steady state.