Classical Advection of Guiding Centers in a Random Magnetic Field

TL;DR

This paper studies how electrons in a 2D gas move under a strong uniform magnetic field combined with a random magnetic field, revealing enhanced conductance due to guiding center advection, with theory matching experiments.

Contribution

It provides a theoretical and experimental analysis of classical advective transport in a 2D electron gas with a random magnetic field, highlighting the role of guiding center advection.

Findings

Enhanced conductance observed under strong uniform magnetic fields.

Scaling behavior of conductance with scattering time matches theory.

Guiding center advection explains the conductance enhancement.

Abstract

We investigate theoretically and experimentally classical advective transport in a 2D electron gas in a random magnetic field. For uniform external perpendicular magnetic fields large compared to the random field we observe a strong enhancement of conductance compared to the ordinary Drude value. This can be understood as resulting from advection of cyclotron guiding centers. For low disorder this enhancement shows non-trivial scaling as a function of scattering time, with consistency between theory and experiment.