Influence of magnetic field offsets on the resistance of magnetic barriers in two-dimensional electron gases

TL;DR

This paper investigates how magnetic field offsets affect the resistance in magnetic barriers within two-dimensional electron gases, revealing asymmetric magnetoresistance features explained by semiclassical simulations.

Contribution

It demonstrates the impact of magnetic field offsets on magnetoresistance and provides a quantitative match with semiclassical models, highlighting the interplay of snake orbits and E x B drift.

Findings

Asymmetric dip in magnetoresistance observed when magnetic field polarity opposes the barrier.

Quantitative agreement between measurements and semiclassical simulations.

Magnetoresistance influenced by snake orbits and E x B drift at Hall bar edges.

Abstract

Magnetic barriers in two-dimensional electron gases are shifted in B space by homogeneous, perpendicular magnetic fields. The magnetoresistance across the barrier shows a characteristic asymmetric dip in the regime where the polarity of the homogeneous magnetic field is opposite to that one of the magnetic barrier. The measurements are in quantitative agreement with semiclassical simulations, which reveal that the magnetoresistance originates from the interplay of snake orbits with E x B drift at the edges of the Hall bar and with elastic scattering.