Conductance of Aharonov--Bohm Rings: From the Discrete to the Continuous Spectrum Limit

TL;DR

This paper investigates how the conductance of mesoscopic Aharonov-Bohm rings varies with statistical ensemble, temperature, and inelastic broadening, revealing ensemble-dependent sign changes and persistent differences up to the Thouless energy.

Contribution

It provides a detailed analysis of the transition from discrete to continuous spectra in mesoscopic rings and how statistical ensembles affect conductance properties.

Findings

Magneto-conductance can change sign between ensembles.

Differences between ensembles persist up to the Thouless energy.

Conductance behavior depends on inelastic broadening and temperature.

Abstract

The dissipative conductance of an array of mesoscopic rings, subject to an a.c. magnetic flux is investigated. The magneto--conductance may change sign between canonical and grand-canonical statistical ensembles, as function of the inelastic level broadening and as function of the temperature. Differences between canonical and grand-canonical ensembles persist up to temperature of the order of the Thouless energy.