Topological magnetic phase in LaMnO${}_3$ (111) bilayer

Abstract

Candidates for correlated topological insulators, originated from the spin-orbit coupling as well as Hubbard type correlation, are expected in the ($111$) bilayer of perovskite-structural transition-metal oxides. Based on the first-principles calculation and tight-binding model, the electronic structure of a LaMnO${}_3$ ($111$) bilayer sandwiched in LaScO${}_3$ barriers has been investigated. For the ideal undistorted perovskite structure, the Fermi energy of LaMnO${}_3$ ($111$) bilayer just stays at the Dirac point, rendering a semi-metal (graphene-like) which is also a half-metal (different from graphene nor previous studied LaNiO${}_3$ ($111$) bilayer). The Dirac cone can be opened by the spin-orbit coupling, giving rise to nontrivial topological bands corresponding to the (quantized) anomalous Hall effect. For the realistic orthorhombic distorted lattice, the Dirac point moves with increasing Hubbard repulsion (or equivalent Jahn-Teller distortion). Finally, a Mott gap opens, establishing a phase boundary between the Mott insulator and topological magnetic insulator. Our calculation finds that the gap opened by spin-orbit coupling is much smaller in the orthorhombic distorted lattice ($\sim$$1.7$ meV) than the undistorted one ($\sim$$11$ meV). Therefore, to suppress the lattice distortion can be helpful to enhance the robustness of topological phase in perovskite ($111$) bilayers.

8 pages, 8 figures

References in corpus (9)

• First Principles Calculation of Anomalous Hall Conductivity in Ferromagnetic bcc Fe
• Dirac materials
• Quantum anomalous Hall effect and related topological electronic states
• Screened hybrid functional applied to 3d^0-->3d^8 transition-metal perovskites LaMO3 (M=Sc-Cu): influence of the exchange mixing parameter on the structural, electronic and magnetic properties
• Origin of the multiferroic spiral spin-order in the RMnO3 perovskites
• Orbital ordering phenomena in $d$- and $f$-electron systems
• Metal-insulator transition in $(LaMn{O}_3{)}_{2n}/(SrMn{O}_3{)}_n$ superlattices
• Electronic structure of (LaNiO${}_3$)${}_2$/(LaAlO${}_3$)${}_N$ heterostructures grown along [111]
• Confinement-driven transitions between topological and Mott phases in (LaNiO3)${}_N$/(LaAlO3)${}_M$(111) superlattices

Cited by in corpus (8)

• Design of Mott and topological phases on buckled 3d-oxide honeycomb lattices
• Transition-Metal Oxide (111) bilayers
• Geometrical lattice engineering of complex oxide heterostructures: a designer approach to emergent quantum states
• Ferroelectricity in [111]-oriented epitaxially strained SrTiO${}_3$ from first principles
• (LaTiO${}_3$)${}_n$/(LaVO${}_3$)${}_n$ as a model system for unconventional charge transfer and polar metallicity
• Phase transitions of LaMnO${}_3$ and SrRuO${}_3$ from DFT + U based machine learning force fields simulations
• Topological end states in two-orbital double-exchange model for colossal magnetoresistive manganites
• Artificial oxide heterostructures with non-trivial topology