The optical Bloch equation for the finite-temperature fluctuations

TL;DR

This paper investigates how quantum and thermal fluctuations influence the optical Bloch equations, providing a framework to analyze finite-temperature effects on quantum systems and their dissipative dynamics.

Contribution

It introduces a method to incorporate finite-temperature fluctuations into the optical Bloch equations for analyzing time-dependent quantum processes.

Findings

Deexcitation approaches equilibrium at zero temperature.

Fluctuations affect the coherence of excitations.

Numerical results demonstrate the impact of temperature on dynamics.

Abstract

In this work, I analyze the quantum fluctuations and the thermal fluctuations in the framework of quantum mechanics. Being recognized as incoherent perturbations with different features, fluctuations of these two types lead to dissipative terms in the optical Bloch equations. The method allows one to use the optical Bloch equation to analyze time-dependent processes in the finite-temperature fluctuations. The numerical results show that the deexcitation is the limit of the equilibration at zero temperature. The impact of the fluctuations on the coherent excitations are also discussed.