Dynamical localization of a particle coupled to a two-level systems thermal reservoir

TL;DR

This paper studies how a particle's motion is affected by a thermal reservoir of two-level systems, revealing low-temperature dynamical localization due to non-Markovian effects, differing from harmonic oscillator baths.

Contribution

It demonstrates the unique dynamical localization of a particle caused by a two-level systems reservoir, highlighting non-Markovian dissipation effects at low temperatures.

Findings

Particle becomes dynamically localized at low temperatures

Localization is due to an effective potential from the reservoir

Behavior differs from harmonic oscillator bath models

Abstract

Using the functional-integral method, we investigate the effect of a two-level systems thermal reservoir on the single particle dynamics. We find that at low temperatures, within the sub-ohmic regime, the particle becomes {}``dynamically'' localized at long times due to an effective potential generated by the particle-reservoir interaction. This behavior is different from the one obtained for the usual bath of harmonic oscillators and is fundamentally related with the non-Markovian character of the dissipative process.