Magneto-transport study of top- and back-gated LaAlO3/SrTiO3heterostructures

W Liu,J.-M Triscone,A Fête,D Li,M Boselli,S Gariglio,D Stornaiuolo

doi:10.1063/1.4921068

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.

Highlights

We report a detailed analysis of magneto-transport properties of top- and back-gated LaAlO3/SrTiO3 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
In order to highlight the difference between the two gate approaches, we plot the mobility μ as a function of the carrier density in Figure 4 for top (panel (a)) and back (panel (b)) gate voltage sweeps. n2D is estimated from the linear Hall effect and the carrier change induced by the capacitor effect, and μ is defined as σ(0)/n2De, where e is the electron charge and σ(0) is the zero-field conductance; μ calculated in this fashion is an effective mobility

Summary

Introduction

We report a detailed analysis of magneto-transport properties of top- and back-gated LaAlO3/SrTiO3 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.

Results

Conclusion