Anisotropic electronic transport of the two-dimensional electron system in Al2O3/SrTiO3 heterostructures

Abstract

Transport measurements on the two dimensional electron system in Al2O3 SrTiO3 heterostructures indicate significant noncrystalline anisotropic behavior below T = 30 K. Lattice dislocations in SrTiO3 and interfacial steps are suggested to be the main sources for electronic anisotropy. Anisotropic defect scattering likewise alters magnetoresistance at low temperature remarkably and influences spin-orbit coupling significantly by the Elliot Yafet mechanism of spin relaxation resulting in anisotropic weak localization. Applying a magnetic field parallel to the interface results in an additional field induced anisotropy of the conductance, which can be attributed to Rashba spin orbit interaction. Compared to LaAlO3 SrTiO3, Rashba coupling seems to be reduced indicating a weaker polarity in Al2O3 SrTiO3 heterostructures.

References in corpus (6)

• Magnetic effects at the interface between nonmagnetic oxides
• Origin of charge density at LaAlO3-on-SrTiO3 hetero-interfaces; possibility of intrinsic doping
• Rashba induced magnetoconductance oscillations in the LaAlO3-SrTiO3 heterostructure
• Giant negative magnetoresistance driven by spin-orbit coupling at the LAO/STO interface
• Intrinsic instability of electronic interfaces with strong Rashba coupling
• Thermally activated recovery of electrical conductivity in LaAlO3/SrTiO3

Cited by in corpus (5)

• Magnetic-field-driven topological transitions in non-centrally-symmetric energy spectrum of 2D electron gas with Rashba-Dresselhaus spin-orbit interaction
• Van Hove scenario of anisotropic transport in a two-dimensional spin-orbit coupled electron gas in an in-plane magnetic field
• A Laser-ARPES View of the 2D Electron Systems at LaAlO3/SrTiO3 and Al/SrTiO3 Interfaces
• High-mobility two-dimensional electron gas in $\gamma$-Al${}_2$O${}_3$/SrTiO${}_3$ heterostructures
• Influence of the vicinal substrate miscut on the anisotropic two-dimensional electronic transport in Al2O3-SrTiO3 heterostructures