Landau-Drude Diamagnetism: Fluctuation, Dissipation and Decoherence

TL;DR

This paper provides a comprehensive dynamical analysis of Landau-Drude diamagnetism, demonstrating the fluctuation-dissipation theorem and exploring coherence-decoherence transitions at zero temperature.

Contribution

It introduces a fully dynamical calculation of susceptibility and autocorrelation functions in dissipative diamagnetism, linking fluctuation-dissipation and coherence phenomena.

Findings

Validated the fluctuation-dissipation theorem in dissipative diamagnetism.

Calculated susceptibility tensor and autocorrelation functions from quantum Langevin equations.

Highlighted the significance of physical details in coherence-to-decoherence transitions.

Abstract

Starting from a quantum Langevin equation (QLE) of a charged particle coupled to a heat bath in the presence of an external magnetic field, we present a fully dynamical calculation of the susceptibility tensor. We further evaluate the position autocorrelation function by using the Gibbs ensemble approach. This quantity is shown to be related to the imaginary part of the dynamical susceptibility, thereby validating the fluctuation-dissipation theorem in the context of dissipative diamagnetism. Finally we present an overview of coherence-to-decoherence transition in the realm of dissipative diamagnetism at zero temperature. The analysis underscores the importance of the details of the relevant physical quantity, as far as coherence to decoherence transition is concerned.