Spin-dependent resistivity at transitions between integer quantum Hall states

TL;DR

This study reveals that the longitudinal resistivity during transitions between integer quantum Hall states in AlAs quantum wells depends on the spin orientation of the Landau level, with significant resistivity enhancement when spins align.

Contribution

It introduces the novel finding that spin orientation influences resistivity at quantum Hall transitions and proposes a new explanation for spike-like features near Landau level crossings.

Findings

Resistivity varies with spin orientation of the Landau level.

Resistivity can increase by an order of magnitude when spins align.

Proposes a new explanation for spike-like features at quantum Hall edges.

Abstract

The longitudinal resistivity at transitions between integer quantum Hall states in two-dimensional electrons confined to AlAs quantum wells is found to depend on the spin orientation of the partially-filled Landau level in which the Fermi energy resides. The resistivity can be enhanced by an order of magnitude as the spin orientation of this energy level is aligned with the majority spin. We discuss possible causes and suggest a new explanation for spike-like features observed at the edges of quantum Hall minima near Landau level crossings.