Magnetotransport of Functional Oxide Heterostructures Affected by Spin-Orbit Coupling: A Tale of Two-Dimensional Systems

TL;DR

This paper investigates magnetotransport phenomena in oxide heterostructures with spin-orbit coupling, revealing complex interplay of weak antilocalization, electron-electron interactions, and multiband effects, including topological Hall effects and quantum band hybridization.

Contribution

It provides a comprehensive analysis of single- and multiband magnetotransport in oxide heterostructures, highlighting the role of electron interactions and band hybridization in topological effects.

Findings

Strong electron-electron interactions suggest a correlated ground state.

Multiband effects significantly influence Hall conductivity.

Weak band coupling causes deviations explained by quantum band hybridization.

Abstract

Oxide heterostructures allow for detailed studies of 2D electronic transport phenomena. Herein, different facets of magnetotransport in selected spin-orbit-coupled systems are analyzed and characterized by their single-band and multiband behavior, respectively. Experimentally, temperature- and magnetic field-dependent measurements in the single-band system BaPbO$_3$/SrTiO$_3$ reveal strong interplay of weak antilocalization (WAL) and electron-electron interaction (EEI). Within a scheme which treats both, WAL and EEI, on an equal footing a strong contribution of EEI at low temperatures is found which suggests the emergence of a strongly correlated ground state. Furthermore, now considering multiband effects as they appear, e.g., in the model system LaAlO$_3$/SrTiO$_3$, theoretical investigations predict a huge impact of filling on the topological Hall effect in systems with intermingled bands. Already weak band coupling produces striking deviations from the well-known Hall conductivity that are explainable in a fully quantum mechanical treatment which builds upon the hybridization of intersecting Hofstadter bands.