Coupling of electronic and structural degrees of freedom in vanadate superlattices

Abstract

Heterostructuring provides different ways to manipulate the orbital degrees of freedom and to tailor orbital occupations in transition metal oxides. However, the reliable prediction of these modifications remains a challenge. Here, we present a detailed investigation of the relationship between the crystal and electronic structure in YVO${}_3$-LaAlO${}_3$ superlattices by combining ab initio theory, scanning transmission electron microscopy, and x-ray diffraction. Density functional theory simulations including an on-site Coulomb repulsion term, accurately predict the crystal structure and in conjunction with x-ray diffraction, provide an explanation for the lifting of degeneracy of the vanadium $d_{xz}$ and $d_{yz}$ orbitals, that was recently observed in this system. In addition, we unravel the combined effects of electronic confinement and octahedral connectivity by disentangling their impact from that of epitaxial strain. Our results demonstrate that the specific orientation of the substrate and the thickness of the YVO${}_3$ slabs in the multilayer, can be utilized to reliably engineer orbital polarization.

10 pages, 6 figures

References in corpus (12)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Magnetic effects at the interface between nonmagnetic oxides
• Oxide Heterostructures for Efficient Solar Cells
• Orbital fluctuations in the different phases of LaVO3 and YVO3
• Evolution of Spin-Orbital-Lattice Coupling in the $R$VO${}_3$ Perovskites
• Crystal structure and high-field magnetism of La2CuO4
• Confinement-driven transitions between topological and Mott phases in (LaNiO3)${}_N$/(LaAlO3)${}_M$(111) superlattices
• One-Dimensional Confinement and Enhanced Jahn-Teller Instability in LaVO${}_3$
• Tuning the Néel temperature in an antiferromagnet: the case of NixCo1-xO microstructures
• Correlated interface electron gas in infinite-layer nickelate versus cuprate films on SrTiO${}_3$(001)
• Magnetism tailored by mechanical strain engineering in PrVO${}_3$ thin films
• Jahn-Teller versus quantum effects in the spin-orbital material LuVO3