Microscopic description of dissipative dynamics of a level crossing transition

TL;DR

This paper investigates how a dissipative environment affects the Landau-Zener transition, revealing temperature-dependent effects and a quantum Zeno phenomenon through a microscopic approach.

Contribution

It introduces a microscopic derivation of the master equation for the LZSM model, capturing temperature effects and strong dissipation impacts not addressed by phenomenological models.

Findings

Survival probability is independent of decay rate at zero temperature.

Strong decay leads to increased survival probability, indicating dynamical decoupling.

High temperature induces a quantum Zeno effect, strongly decoupling the initial state.

Abstract

We analyze the effect of a dissipative bosonic environment on the Landau-Zener-Stuckelberg-Majorana (LZSM) level crossing model by using a microscopic approach to derive the relevant master equation. For an environment at zero temperature and weak dissipation our microscopic approach confirms the independence of the survival probability on the decay rate that has been predicted earlier by the simple phenomenological LZSM model. For strong decay the microscopic approach predicts a notable increase of the survival probability, which signals dynamical decoupling of the initial state. Unlike the phenomenological model our approach makes it possible to study the dependence of the system dynamics on the temperature of the environment. In the limit of very high temperature we find that the dynamics is characterized by a very strong dynamical decoupling of the initial state - temperature-induced quantum Zeno effect.