Shubnikov-de Haas-like Quantum Oscillations in Artificial One-Dimensional LaAlO3/SrTiO3 Electron Channels

TL;DR

This study reports SdH-like quantum oscillations in artificially created quasi-1D LaAlO3/SrTiO3 channels, revealing their origin from magnetic depopulation of subbands and suggesting a new understanding of oscillations in 2D systems.

Contribution

It demonstrates the existence of SdH-like oscillations in artificially fabricated quasi-1D channels and links these to magnetic depopulation, providing insight into their origin in 2D heterostructures.

Findings

SdH-like oscillations observed in quasi-1D LaAlO3/SrTiO3 channels

Oscillations attributed to magnetic depopulation of subbands

Implication that 2D oscillations may originate from quasi-1D channels

Abstract

The widely reported magnetoresistance oscillations in LaAlO3/SrTiO3 heterostructures have invariably been attributed to the Shubnikov-de Haas (SdH) effect, despite a pronounced inconsistency with low-field Hall resistance measurements. Here we report SdH-like resistance oscillations in quasi-1D electron waveguides created at the LaAlO3/SrTiO3 interface by conductive atomic force microscopy lithography. These oscillations can be directly attributed to magnetic depopulation of magnetoelectric subbands. Our results suggest that the SdH oscillations in 2D SrTiO3-based systems may originate from naturally forming quasi-1D channels.