Structural, Electronic and Magnetic Properties of Bulk and Epitaxial LaCoO${}_3$ through Diffusion Monte Carlo

Abstract

Magnetism in lanthanum cobaltite (LCO, LaCoO${}_3$) appears to be strongly dependent on strain, defects, and nanostructuring. LCO on strontium titanate (STO, SrTiO${}_3$) is a ferromagnet with an interesting strain relaxation mechanism that yields a lattice modulation. However, the driving force of the ferromagnetism is still controversial. Experiments debate between a vacancy-driven or strain-driven mechanism for the ferromagnetism of epitaxial LCO. We found that a weak lateral modulation of the superstructure is sufficient to promote ferromagnetism. We find that ferromagnetism appears under uniaxial compression and expansion. Although earlier experiments suggest that bulk LCO is nonmagnetic, we find an antiferromagnetic ground state for bulk LCO. We discuss the recent experiments which indicate a more complicated picture for bulk magnetism and a closer agreement with our calculations. Role of defects are also discussed through excited state calculations.

12 pages, 9 figures

References in corpus (25)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Restoring the density-gradient expansion for exchange in solids and surfaces
• Generalized gradient approximation for solids and their surfaces
• Continuum variational and diffusion quantum Monte Carlo calculations
• Jastrow correlation factor for atoms, molecules, and solids
• QMCPACK : An open source ab initio Quantum Monte Carlo package for the electronic structure of atoms, molecules, and solids
• Inhomogeneous backflow transformations in quantum Monte Carlo calculations
• Strain-Induced Spin States in Atomically Ordered Cobaltites
• 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
• Evaluating transition-metal oxides within DFT-SCAN and SCAN+U frameworks for solar thermochemical applications
• Structural effects on the spin-state transition in epitaxially strained LaCoO${}_3$ films
• Spin state transition and covalent bonding in LaCoO3
• Phase Stability of TiO${}_2$ Polymorphs from Diffusion Quantum Monte Carlo
• Excitation energies from diffusion Monte Carlo using selected Configuration Interaction nodes
• Suppression of the ferromagnetic state in LaCoO3 films by rhombohedral distortion
• Wave functions for quantum Monte Carlo calculations in solids: Orbitals from density functional theory with hybrid exchange-correlation functionals
• Structural Stability and Defect Energetics of ZnO from Diffusion Quantum Monte Carlo
• Interaction-induced quantum anomalous Hall phase in (111) bilayer of LaCoO${}_3$
• Cohesive energy and structural parameters of binary oxides of groups IIA and IIIB from diffusion quantum Monte Carlo
• Excited-state diffusion Monte Carlo calculations: a simple and efficient two-determinant ansatz
• Variational Excitations in Real Solids: Optical Gaps and Insights into Many-Body Perturbation Theory
• The unusual magnetism of nanoparticle LaCoO3
• Charge-transfer excited states: Seeking a balanced and efficient wave function ansatz in variational Monte Carlo
• The effects of Co3O4 on the Structure and Unusual Magnetism of LaCoO3
• An efficient hybrid orbital representation for quantum Monte Carlo calculations

Cited by in corpus (8)

• A first-principles Quantum Monte Carlo study of two-dimensional (2D) GaSe
• Systematic DFT+U and Quantum Monte Carlo benchmark of magnetic two-dimensional (2D) CrX${}_3$ (X = I, Br, Cl, F)
• Spin State Disproportionation in Insulating Ferromagnetic LaCoO3 Epitaxial Thin Films
• The intrinsic ferromagnetism of two-dimensional (2D) MnO${}_2$ revisited: A many-body Quantum Monte Carlo and DFT+U study
• Tunable Ferromagnetism in LaCoO3 Epitaxial Thin Films
• A Quantum Monte Carlo study of the structural, energetic, and magnetic properties of two-dimensional (2D) H and T phase VSe${}_2$
• A pathway towards high throughput Quantum Monte Carlo simulations for alloys: A case study of two-dimensional (2D) $Ga{S}_{x}S{e}_{1-x}$
• Toward improved property prediction of 2D materials using many-body quantum Monte Carlo methods