Non-Markovianity of a quantum emitter in front of a mirror

Understand

We consider a quantum emitter ("atom") radiating in a one-dimensional (1D) photonic waveguide in the presence of a single mirror, resulting in a delay differential equation for the atomic amplitude.

• We carry out a systematic analysis of the non-Markovian (NM) character of the atomic dynamics in terms of refined, recently developed notions of quantum non-Markovianity such as indivisibility and information back-flow.
• NM effects are quantified as a function of the round-trip time and phase shift associated with the atom-mirror optical path.
• We find, in particular, that unless an atom-photon bound state is formed a finite time delay is always required in order for NM effects to be exhibited.