High field magneto-transport in two-dimensional electron gas LaAlO3/SrTiO3

TL;DR

This study investigates the high magnetic field transport properties of LaAlO3/SrTiO3 interfaces, revealing their two-dimensional nature, Rashba spin-orbit coupling effects, and multi-band contributions to charge transport.

Contribution

It provides new insights into the magneto-transport behavior of LaAlO3/SrTiO3, highlighting the role of Rashba spin-orbit coupling and multi-band effects under high magnetic fields.

Findings

Two-dimensional charge transport confirmed by sample rotation.

Observation of oscillations in magnetoresistance linked to Rashba spin-orbit coupling.

Discrepancy between carrier densities from different measurement methods explained by multi-band transport.

Abstract

Transport properties of the complex oxide LaAlO3/SrTiO3 interface are investigated under high magnetic field (55T). By rotating the sample with respect to the magnetic field, the two-dimensional nature of charge transport is clearly established. Small oscillations of the agnetoresistance with altered periodicity are observed when plotted versus inverse magnetic field. We attribute this effect to Rashba spin-orbit coupling which remains consistent with large negative magnetoresistance when the field is parallel to the sample plane. A large inconsistency between the carrier density extracted from Shubnikov-de Haas analysis and from the Hall effect is explained by the contribution to transport of at least two bands with different mobility.