Random matrix approach to `nonuniversal' conductance

TL;DR

This paper uses an extended random matrix approach to explain the system-dependent conductance quantization steps observed in high-quality quantum wires, revealing a universal behavior governed by a single parameter.

Contribution

It introduces an extended random matrix model that accounts for nonuniversal conductance quantization in quantum wires, highlighting a single parameter controlling the quantization steps.

Findings

Quantization steps depend on a single system parameter.

The behavior is effectively universal across a class of mesoscopic systems.

The model explains experimental observations of conductance variability.

Abstract

Recent experiments on the conductance of high quality quantum wires have revealed an unexpected feature: the quantization step of the conductance is apparently system dependent. We provide the understanding of this behaviour using the appropriately extended random matrix approach. A single additional parameter governs the size of the conductance quantization steps. In effect the behaviour seems to remain `universal', generic for the conductance of a class of mesoscopic systems.