Mesoscopic Spin-Magnetism

TL;DR

This paper studies the spin-magnetism in mesoscopic metallic grains, analyzing how spectral fluctuations and electron interactions cause non-linear magnetic responses, with implications for understanding quantum energy level statistics.

Contribution

It introduces a combined numerical and analytical approach to quantify magnetic response corrections and proposes an experiment to measure interaction coupling constants.

Findings

Temperature dependence of corrections calculated

Reproducible magnetization fluctuations observed

Proposal for measuring interaction coupling constant

Abstract

We investigate the spin-magnetism of mesoscopic metallic grains. In the average response of an ensemble of grains there are corrections to macroscopic behaviour due to both spectral fluctuations and electron-electron interactions. These corrections are a non-linear function of the magnetic field. Their temperature dependence is calculated numerically and analytically. An experiment is proposed to measure the unknown interaction coupling constant in the cooper channel. For a single sample the magnetization is found to fluctuate reproducibly about the mean. These fluctuations directly probe the energy level statistics.