Magneto-transport study of top- and back-gated LaAlO$_3$/SrTiO$_3$ heterostructures

TL;DR

This study investigates how top and back gating influence the magneto-transport properties of LaAlO$_3$/SrTiO$_3$ heterostructures, revealing distinct effects on electron mobility and carrier density, and examining changes in spin-orbit interaction.

Contribution

It provides a detailed analysis of gating effects on magneto-transport and spin-orbit interaction in LaAlO$_3$/SrTiO$_3$ heterostructures, highlighting the different roles of top and back gates.

Findings

Back gate significantly alters electron mobility.

Top gate primarily modulates carrier density.

Spin-orbit interaction evolves with gating.

Abstract

We report a detailed analysis of magneto-transport properties of top- and back-gated LaAlO$_3$/SrTiO$_3$ heterostructures. Efficient modulation in magneto-resistance, carrier density, and mobility of the two-dimensional electron liquid present at the interface is achieved by sweeping top and back gate voltages. Analyzing those changes with respect to the carrier density tuning, we observe that the back gate strongly modifies the electron mobility while the top gate mainly varies the carrier density. The evolution of the spin-orbit interaction is also followed as a function of top and back gating.