Continuum shell model: From Ericson to conductance fluctuations

TL;DR

This paper develops a continuum shell model for mesoscopic systems that accounts for strong interactions and continuum coupling, explaining resonance formation, statistical properties, and conductance fluctuations.

Contribution

It introduces a new consistent continuum shell model that integrates fermion interactions with continuum effects for various physical systems.

Findings

Describes universal conductance fluctuation properties

Analyzes Ericson resonance fluctuations

Models correlations of scattering cross sections

Abstract

We discuss an approach for studying the properties of mesoscopic systems, where discrete and continuum parts of the spectrum are equally important. The approach can be applied (i) to stable heavy nuclei and complex atoms near the continuum threshold, (ii) to nuclei far from the region of nuclear stability, both of the regions being of great current interest, and (iii) to mesoscopic devices with interacting electrons. The goal is to develop a new consistent version of the continuum shell model that simultaneously takes into account strong interaction between fermions and coupling to the continuum. Main attention is paid to the formation of compound resonances, their statistical properties, and correlations of the cross sections. We study the Ericson fluctuations of overlapping resonances and show that the continuum shell model nicely describes universal properties of the conductance fluctuations.