Phase diagrams of voltage-gated oxide interfaces with strong Rashba coupling

Abstract

We propose a model for the two-dimensional electron gas formed at the interface of oxide heterostructures that includes a Rashba spin-orbit coupling proportional to an electric field oriented perpendicularly to the interface. Taking into account the electron density dependence of this electric field confining the electron gas at the interface, we report the occurrence of a phase separation instability (signaled by a negative compressibility) for realistic values of the spin-orbit coupling and of the electronic band-structure parameters at zero temperature. We extend the analysis to finite temperatures and in the presence of an in-plane magnetic field, thereby obtaining two phase diagrams which exhibit a phase separation dome. By varying the gating potential the phase separation dome may shrink and vanish at zero temperature into a quantum critical point where the charge fluctuates dynamically. Similarly the phase separation may be spoiled by a planar magnetic field even at zero temperature leading to a line of quantum critical points.

17 pages, 17 figures

References in corpus (13)

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• Oxide superlattices with alternating p and n interfaces
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• Multi-band superconductivity and nanoscale inhomogeneity at oxide interfaces
• Phase diagram for Coulomb-frustrated phase separation in systems with negative short-range compressibility
• Evidence for charge-vortex duality at the LaAlO${}_3$/SrTiO${}_3$ interface
• Charge density distribution and optical response of the LaAlO3/SrTiO3 interface
• Spin-Orbit Coupling in LaAlO${}_3$/SrTiO${}_3$ interfaces: Magnetism and Orbital Ordering

Cited by in corpus (26)

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• Topological superconductivity and unconventional pairing in oxide interfaces
• Giant negative magnetoresistance driven by spin-orbit coupling at the LAO/STO interface
• Phase separation from electron confinement at oxide interfaces
• New insights into the electron trapping mechanism in LaAlO_3 / SrTiO3 heterostructures
• Multi-band theory of superconductivity at the LaAlO${}_3$/SrTiO${}_3$ interface
• Inhomogeneous multi-carrier superconductivity at LaXO3/SrTiO3 (X=Al or Ti) oxide interfaces
• Negative electronic compressibility and nanoscale inhomogeneity in ionic-liquid gated two-dimensional superconductors
• Pseudo-gap in tunneling spectra as a signature of inhomogeneous superconductivity in oxide interfaces
• Capacitance and compressibility of heterostructures with strong electronic correlations
• Intrinsic spin Hall effect in systems with striped spin-orbit coupling
• Semiclassical theory of anisotropic transport at LaAlO3/SrTiO3 interfaces under in-plane magnetic field
• Multigaps superconductivity at unconventional Lifshitz transition in a 3D Rashba heterostructure at atomic limit
• Theoretical models of Rashba spin splitting in asymmetric SrTiO3-based heterostructures
• Magnetic and transport signatures of Rashba spin-orbit coupling on the ferromagnetic Kondo lattice model in two dimensions
• Anomalous transport near the Lifshitz transition at the LaAlO${}_3$/SrTiO${}_3$ interface
• Possible mechanisms of electronic phase separation in oxide interfaces
• Density inhomogeneities and Rashba spin-orbit coupling interplay in oxide interfaces
• Current-induced spin polarization in isotropic k-cubed Rashba model: Theoretical study for p-doped semiconductor heterostructures and perovskite oxides interfaces
• Helical currents in metallic Rashba strips
• Phase separation and long wave-length charge instabilities in spin-orbit coupled systems
• Spin-orbit controlled quantum capacitance of a polar heterostructure
• Interplay between density and superconducting quantum critical fluctuations
• Superfluid response of two-dimensional filamentary superconductors
• Transport properties of Rashba conducting strips coupled to magnetic moments with spiral order