Bond current in a mesoscopic ring -- signature of decoherence due to classical and quantum noise

TL;DR

This paper investigates how classical and quantum noise affect the bond current in a mesoscopic ring, revealing the coherence-to-incoherence transition and providing insights into decoherence mechanisms in quantum systems.

Contribution

It offers an exact calculation of bond current in a mesoscopic ring under noise, comparing classical and quantum noise effects within a unified framework.

Findings

Coherence-to-incoherence transition identified under noise influence

Quantum noise modeled by spin-boson Hamiltonian shows distinct decoherence signatures

Classical noise types differently impact the bond current and coherence properties

Abstract

A three-site mesoscopic ring provides an ideal setting for an exact calculation of the bond current when the ring is threaded by an Aharonov-Bohm flux. The bond current is a measurable outcome of the coherent properties of the quantum phase. However the coherence is impeded by noise when the ring is put in contact with an environment. This coherence-to-incoherence transition is analyzed in detail here for both classical (Gaussian and telegraphic) and quantum noise and a comparative assessment is made when the quantum noise is governed by a spin-boson Hamiltonian of dissipative quantum mechanics.