Giant tunability of the two-dimensional electron gas at the interface of gamma-Al2O3/SrTiO3

Abstract

Herein, we reported giant tunability of the physical properties of 2DEGs at the spinel/perovskite interface of γ-Al2O3/SrTiO3 (GAO/STO). By modulating the carrier density thus the band filling with ionic-liquid gating, the system experiences a Lifshitz transition at a critical carrier density of 3E13 cm-2, where a remarkably strong enhancement of Rashba spin-orbit interaction and an emergence of Kondo effect at low temperatures are observed. Moreover, as the carrier concentration depletes with decreasing gating voltage, the electron mobility is enhanced by more than 6 times in magnitude, leading to the observation of clear quantum oscillations. The great tunability of GAO/STO interface by EDLT gating not only shows promise for design of oxide devices with on-demand properties, but also sheds new light on the electronic structure of 2DEG at the non-isostructural spinel/perovskite interface.

Nano Letters 2017

References in corpus (12)

• Magnetic effects at the interface between nonmagnetic oxides
• Electric Field Control of the LaAlO${}_3$/SrTiO${}_3$ Interface Ground State
• Theory of spin-orbit coupling at LaAlO3/SrTiO3 interfaces and SrTiO3 surfaces
• A high-mobility two-dimensional electron gas at the heteroepitaxial spinel/perovskite complex oxide interface of γ-Al2O3/SrTiO3
• Visible light enhanced field effect at LaAlO3/SrTiO3 interface
• A high-mobility electronic system at an electrolyte-gated oxide surface
• Gate-tunable band structure of the LaAlO${}_3$-SrTiO${}_3$ interface
• Anomalous orbital structure in a spinel-perovskite interface $\gamma$-Al${}_2$O${}_3$/SrTiO${}_3$
• Quantum longitudinal and Hall transport at the LaAlO3/SrTiO3 interface at low electron densities
• Suppressed carrier density for the patterned high mobility two-dimensional electron gas at gamma-Al2O3/SrTiO3 heterointerfaces
• Signature of enhanced spin-orbit interaction in the magnetoresistance of LaTiO${}_3$/SrTiO${}_3$ interfaces on $\delta$-doping
• Influence of oxygen pressure and aging on LaAlO3 films grown by pulsed laser deposition on SrTiO3 substrates

Cited by in corpus (3)

• Magnetic and electronic properties at the gamma-Al2O3/SrTiO3 interface
• Band-Order Anomaly at the γ-Al2O3/SrTiO3 Interface Drives the Electron-Mobility Boost
• Ferroelectric control of spin-polarized two-dimensional electron gas