Related papers: Orbital reconstruction in nonpolar tetravalent tra…
In oxide heterostructures, different materials are integrated into a single artificial crystal, resulting in a breaking of inversion-symmetry across the heterointerfaces. A notable example is the interface between polar and non-polar…
Motivated by recent experimental progress in transition metal oxides with the K$_2$NiF$_4$ structure, we investigate the magnetic and orbital ordering in $\alpha$-Sr$_2$CrO$_4$. Using first principles calculations, first we derive a…
In complex transition metal oxide heterostructures of physically dissimilar perovskite compounds, interface phenomena can lead to novel physical properties not observed in either of their constituents. This remarkable feature opens new…
Ir-based materials have drawn much attention due to the observation of insulating phase believed to be driven by spin-orbit coupling while Ir 5$d$ states are expected to be weakly correlated due to their large orbital extensions. IrO$_2$, a…
Layered 5$d$ transition iridium oxides, Sr$_2$(Ir,Rh)O$_4$, are described as unconventional Mott insulators with strong spin-orbit coupling. The undoped compound, Sr$_2$IrO$_4$, is a nearly ideal two-dimensional pseudospin-$1/2$ Heisenberg…
The shape of 3$d$-orbitals often governs the electronic and magnetic properties of correlated transition metal oxides. In the superconducting cuprates, the planar confinement of the $d_{x^2-y^2}$ orbital dictates the two-dimensional nature…
The (SrTiO$_3$)$_m$/(SrVO$_3$)$_n$ $d^0-d^1$ multilayer system is studied with first principles methods through the observed insulator-to-metal transition with increasing thickness of the SrVO$_3$ layer. When correlation effects with…
Multilayer (TiO$_2$)$_m$/(VO$_2$)$_n$ nanostructures ($d^1$ - $d^0$ interfaces with no polar discontinuity) show a metal-insulator transition with respect to the VO$_2$ layer thickness in first principles calculations. For $n$ $\geq$ 5…
Orbital reconstruction at interfaces between YBa2Cu3O6 and SrO-terminated SrTiO3 is studied using local spin density approximation (LSDA) with intra-atomic Coulomb repulsion (LSDA+U). The change of population of interfacial Cu 3d orbitals…
In electronic solids with strong spin-orbit interactions (SOIs), the spin and orbital degrees of freedom of an electron are quantum mechanically entangled, which may result in an exotic multipolar order instead of a conventional dipolar…
The 3d electronic structure and phase transition in pure and Cr doped V2O3 are theoretically investigated in relation to the 3d spin-orbit interaction and lattice distortion. A model consisting of the nearest-neighbor V ion pair with full…
The electronic structure of the vanadium dioxide VO_2 in the tetragonal R and two monocinic M_1 and M_2 structural modifications was calculated in frames of the local-density functional (LDA) approach and the LSDA + U formalism of…
Resonant x-ray diffraction performed at the $\rm L_{II}$ and $\rm L_{III}$ absorption edges of Ru has been used to investigate the magnetic and orbital ordering in Ca$_2$RuO$_4$ single crystals. A large resonant enhancement due to electric…
The diverse functionality emerging at oxide interfaces calls for a fundamental understanding of the mechanisms and control parameters of electronic reconstructions. Here, we explore the evolution of electronic phases in…
The application of modern layer-by-layer growth techniques to transition-metal oxide materials raises the possibility of creating new classes of materials with rationally designed correlated electron properties. An important step toward…
We investigate two-dimensional trilayered quantum systems with multi-orbital conduction bands by focusing on the role played by the layer degree of freedom in setting the character of nodal line semimetals. The layer index can label the…
We investigate the interplay between Coulomb driven orbital order and octahedral distortions in strongly correlated Mott insulators due to orbital dilution, i.e., doping by metal ions without an orbital degree of freedom. In particular, we…
Transition-metal ions with $5d^2$ electronic configuration in a cubic crystal field are prone to have a vanishing dipolar magnetic moment but finite higher-order multipolar moments, and they are expected to exhibit exotic physical…
We introduce and investigate the multiband $d-p$ model describing a IrO$_4$ layer (such as realized in Ba$_2$IrO$_4$) where all $34$ orbitals per unit cell are partly occupied, i.e., $t_{2g}$ and $e_g$ orbitals at iridium and $2p$ orbitals…
The collective behavior of correlated electrons in the VO$_2-$interface layer of LaVO$_3$/SrTiO$_3$ heterostructure is studied within a quarter-filled $t_{2g}$-orbital Hubbard model on a square lattice. We argue that the ground state is…