Stochastic representation of quantum interactions and two-lewel systems

TL;DR

This paper introduces a stochastic formalism for quantum interactions, enabling the replacement of complex quantum systems with equivalent classical random sources, and applies it to two-level systems in thermal baths to analyze non-Markovian effects.

Contribution

The paper develops a stochastic representation framework for quantum interactions and applies it to analyze two-level systems in thermal environments, highlighting non-Markovian dynamics.

Findings

Identification of strong-coupling non-Markovian effects

Observation of long-living fluctuations in susceptibility

Demonstration of stochastic formalism applicability to quantum systems

Abstract

Stochastic representation for interaction of quantum systems is formulated which allows to replace some of them by equivalent but purely commutative random sources. The formalism is applied to two-level systems interacting with Gaussian thermal bath. Strong-coupling non-Marcovian effects and besides long-living fluctuations in common susceptibility of two systems subjected to the same bath are considered.