Strong spin-orbit coupling and magnetism in (111) (La${}_{0.3}$Sr${}_{0.7}$)(Al${}_{0.65}$Ta${}_{0.35})$/SrTiO${}_3$

Abstract

Strong correlations, multiple lattice degrees of freedom, and the ease of doping make complex oxides a source of great research interest. Complex oxide heterointerfaces break inversion symmetry and can host a two dimensional carrier gas, which can display a variety of coexisting and competing phenomena. In the case of heterointerfaces based on SrTiO${}_3$, many of these phenomena can be effectively tuned by using an electric gate, due to the large dielectric constant of SrTiO${}_3$. Most studies so far have focused on (001) oriented heterostructures; however, (111) oriented heterostructures have recently gained attention due to the possibility of finding exotic physics in these systems due their hexagonal surface crystal symmetry. In this work, we use magnetoresistance to study the evolution of spin-orbit interaction and magnetism in a new system, (111) oriented (La${}_{0.3}$Sr${}_{0.7}$)(Al${}_{0.65}$Ta${}_{0.35}$)/SrTiO${}_3$. At more positive values of the gate voltage, which correspond to high carrier densities, we find that transport is multiband, and dominated by high mobility carriers with a tendency towards weak localization. At more negative gate voltages, the carrier density is reduced, the high mobility bands are depopulated, and weak antilocalization effects begin to dominate, indicating that spin-orbit interaction becomes stronger. At millikelvin temperatures, and gate voltages corresponding to the strong spin-orbit regime, we observe hysteresis in magnetoresistance, indicative of ferromagnetism in the system. Our results suggest that in the (111) (La${}_{0.3}$Sr${}_{0.7}$)(Al${}_{0.65}$Ta${}_{0.35}$)/SrTiO${}_3$ system, low mobility carriers which experience strong spin-orbit interactions participate in creating magnetic order in the system.

arXiv comment15 pages, 3 figures

References in corpus (38)

• Magnetic effects at the interface between nonmagnetic oxides
• Emergent Phenomena Induced by Spin-Orbit Coupling at Surfaces and Interfaces
• Tunable Rashba spin-orbit interaction at oxide interfaces
• Direct imaging of the coexistence of ferromagnetism and superconductivity at the LaAlO3/SrTiO3 interface
• Unveiling a two-dimensional electron gas with universal subbands at the surface of SrTiO3
• Non-saturating magnetoresistance in heavily disordered semiconductors
• Coexistence of superconductivity and ferromagnetism in two dimensions
• Interface engineering of quantum Hall effects in digital transition metal oxide heterostructures
• A Universal Critical Density Underlying the Physics of Electrons at the LaAlO3/SrTiO3 Interface
• Two-dimensional quantum oscillations of the conductance at LaAlO3/SrTiO3 interfaces
• High mobility conduction at (110) and (111) LaAlO3/SrTiO3 interfaces
• Ferromagnetic exchange, spin-orbit coupling and spiral magnetism at the LaAlO_3/SrTiO_3 interface
• Shubnikov-de Haas oscillations in SrTiO3\LaAlO3 interface
• Room-Temperature Electronically-Controlled Ferromagnetism at the LaAlO3/SrTiO3 Interface
• Unexpected Anisotropic Two Dimensional Electron Gas at the LaAlO3/SrTiO3 (110) Interface
• Phase diagram of electrostatically doped Strontium Titanate (SrTiO3)
• Control of a two-dimensional electron gas on SrTiO3(111) by atomic oxygen
• Rashba induced magnetoconductance oscillations in the LaAlO3-SrTiO3 heterostructure
• Massive symmetry breaking in LaAlO${}_3$/SrTiO${}_3$(111) quantum wells: a three-orbital, strongly correlated generalization of graphene
• Carrier-controlled ferromagnetism in SrTiO3
• Orientational tuning of the Fermi sea of confined electrons at the SrTiO3 (110) and (111) surfaces
• Six-fold crystalline anisotropic magnetoresistance in the (111) LaAlO${}_3$/SrTiO${}_3$ oxide interface
• Magnetoresistance of 2D and 3D Electron Gas in LaAlO3/SrTiO3 Heterostructures: Influence of Magnetic Ordering, Interface Scattering and Dimensionality
• Link between the Superconducting Dome and Spin-Orbit Interaction in the (111) LaAlO${}_3$/SrTiO${}_3$ Interface
• Spirals and skyrmions in two dimensional oxide heterostructures
• The Effect of Polar Fluctuation and Lattice Mismatch on Carrier Mobility at Oxide Interfaces
• Evidence for charge-vortex duality at the LaAlO${}_3$/SrTiO${}_3$ interface
• Hysteretic Magnetotransport in SmB6 at Low Magnetic Fields
• Magnetotransport Measurements of the Surface States of Samarium Hexaboride using Corbino Structures
• Controlling Kondo-like Scattering at the SrTiO3-based Interfaces
• Anomalous magnetic ground state in LaAlO3/SrTiO3 interface probed by transport through nanowires
• Anisotropic, multi-carrier transport at the (111) LaAlO${}_3$/SrTiO${}_3$ interface
• Magnetoresistance in the superconducting state at the (111) LaAlO${}_3$/SrTiO${}_3$ interface
• Superconductivity and Frozen Electronic States at the (111) LaAlO${}_3$/SrTiO${}_3$ Interface
• Signatures of Electronic Nematicity in (111) LaAlO${}_3$/SrTiO${}_3$ Interfaces
• Electrical Properties and Subband Occupancy at the (La,Sr)(Al,Ta)O${}_3$/SrTiO${}_3$ Interface
• Electrostatic tuning of magnetism at the conducting (111) (La${}_{0.3}$Sr${}_{0.7}$)(Al${}_{0.65}$Ta${}_{0.35}$)/SrTiO${}_3$ interface
• The Vortex Signature of Discrete Ferromagnetic Dipoles at the LaAlO${}_3$/SrTiO${}_3$ Interface

Cited by in corpus (3)

• Disentangling spin-orbit coupling and local magnetism in a quasi-two-dimensional electron system
• Observation of zero-field transverse resistance in AlO${}_x$/SrTiO${}_3$ interface devices
• Low temperature magnetoresistance of (111) (La${}_{0.3}$Sr${}_{0.7}$)(Al${}_{0.65}$Ta${}_{0.35}$)/SrTiO${}_3$