Correction factor in non-diffusive Hall magnetometry

TL;DR

This paper investigates how the correction factor in Hall magnetometry varies with sample geometry and electron mean free path, revealing that assuming a constant value can cause significant measurement errors.

Contribution

It demonstrates the dependence of the correction factor on sample geometry and electron mean free path in non-diffusive regimes, challenging the common approximation of a constant correction factor.

Findings

Correction factor alpha varies with geometry and mean free path.

Constant approximation of alpha can lead to large errors.

Dependence of alpha is complex and nontrivial.

Abstract

It is demonstrated how the correction factor alpha used in Hall magnetometry of localized magnetic field profiles depends on the sample geometry and on the electron mean free path, in the quasi-ballistic and ballistic regimes, for weak and strong magnetic field regimes. The frequently used approximation of a constant correction factor close to 1 is generally not justified, especially in the case of bipolar magnetic field profiles and may lead to large errors in the determination of the magnitude of the magnetic fields. Rather, alpha depends in a nontrivial way on the parameters of both the magnetic structure and the Hall cross.