Dissipative evolution of a two-level system through a geometry-based classical mapping

TL;DR

This paper introduces a geometry-based formalism for mapping two-level systems to study their dissipative dynamics, revealing transitions between oscillatory and tunneling-suppressed behaviors and environment-induced asymmetry.

Contribution

The work develops a novel geometry-based mapping formalism for two-level systems, enabling analysis of their dissipative dynamics and environment interactions with new insights.

Findings

Identified a transition between oscillatory and tunneling-suppressed dynamics by varying coupling.

Observed environment-assisted asymmetry in a symmetric two-level system.

Demonstrated damping effects analogous to harmonic oscillator baths in the weak coupling limit.

Abstract

In this manuscript, we introduce a geometry-based formalism to obtain a Meyer-Miller-Stock-Thoss mapping in order to study the dynamics of both isolated and interacting two-level systems. After showing the description of the isolated case using canonically conjugate variables, we implement an interaction model by bilinearly coupling the corresponding population differences {\it \`a la} Caldeira-Leggett, showing that the dynamics behave as a Gross-Pitaevskii-like one. We also find a transition between oscillatory and tunneling-suppressed dynamics that can be observed by varying the coupling constant. After extending our model to the {\it system plus environment} case, where the environment is considered as a collection of two-level systems, we show tunneling-suppressed dynamics in the strong coupling limit and the usual damping effect similar to that of a harmonic oscillator bath in the weak coupling one. Finally, we observe that our interacting model turns an isolated symmetric two-level system into an environment-assisted asymmetric one.