Emergence of non-Markovianity in the emission process of an atom in a half-cavity

TL;DR

This paper investigates how non-Markovian effects emerge during the early emission process of a two-level atom near a perfect mirror, identifying a parameter threshold that distinguishes Markovian from non-Markovian dynamics.

Contribution

It introduces a threshold criterion in parameter space for the emergence of non-Markovianity in atom emission near a mirror, focusing on early-time dynamics.

Findings

Non-Markovianity appears after a certain parameter threshold.

A clear boundary separates Markovian and non-Markovian regimes.

Early-time emission dynamics are significantly affected by the mirror's presence.

Abstract

We study quantum non-Markovianity in the early stage of the emission process of a two-level atom coupled to a semi-infinite waveguide, where the waveguide termination behaves as a perfect mirror. Specifically, we restrict to the analysis of the process for times shorter than twice the time delay t_d, where t_d is the duration of a round trip along the atom-mirror path. We show the emergence of a threshold in the parameters space separating the Markovian and non-Markovian regions.