Magnetic Response of Disordered Ballistic Quantum Dots

TL;DR

This paper investigates how static disorder influences the magnetic susceptibility of mesoscopic quantum dots, revealing a disorder-independent paramagnetic response consistent with experimental observations.

Contribution

It introduces a semiclassical approach to analyze the magnetic response of disordered quantum dots, highlighting the role of long trajectories and disorder effects.

Findings

Disorder induces a large linear paramagnetic susceptibility.

Susceptibility is independent of disorder strength.

Crossover to nonlinear response is characterized.

Abstract

The weak field average magnetic susceptibility of square shaped mesoscopic conductors is studied within a semiclassical framework. Long semiclassical trajectories are strongly affected by static disorder and differ sharply from those of clean systems. They give rise to a large linear paramagnetic susceptibility which is disorder independent and in agreement with recent experiments. The crossover field to a nonlinear susceptibility is discussed.