Related papers: Dependence of band gaps in d-electron perovskite o…
With their broad range of magnetic, electronic and structural properties, transition metal perovskite oxides ABO3 have long served as a platform for testing condensed matter theories. In particular, their insulating character - found in…
Compounds having an odd number of electrons with the same orbital character in occupied and unoccupied band edge states would be expected to have band degeneracy at the Fermi energy, making such reference system metals. Yet, many ABO3 oxide…
It is shown that ferromagnetic ordering in metals is associated with an opening of the energy pseudogap. This energy pseudogap belongs to a d-band type in d-metals and to an sp-band type in f-metals. A relation between the magnetic energy…
We describe a variational theory of multi-band two-dimensional electron gases that captures the interplay between electrostatic confining potentials, orbital-dependent interlayer electronic hopping and electron-electron interactions, and…
This paper is an overview of some recent work done on the double perovskites. We discuss the physics of selected double perovskite compounds emphasizing the relevant interactions and resulting observable phenomena such as the magnetic order…
The 3$d$-5$d$ based double perovskites offer an ideal playground to study the interplay between electron correlation ($U$) and spin-orbit coupling (SOC) effect, showing exotic physics. The Sr$_2$FeIrO$_6$ is an interesting member in this…
In recent decades, novel magnetism of $d$- and $f$-electron compounds has been discussed very intensively both in experimental and theoretical research fields of condensed matter physics. It has been recognized that those material groups…
Domain wall morphologies in ferroelectrics are believed to be largely shaped by electrostatic forces. Here, we show that for conducting domain walls, the morphology also depends on the details of the charge-carrier band structure. For…
Density functional theory (DFT) based calculations have been conducted to draw a broad picture of pressure induced band structure evolution in various phases of organic and inorganic halide perovskite materials. Under a wide range of…
We investigate the effect of pressure on the electronic and magnetic states of CdV$_2$O$_4$ by using ab initio electronic structure calculations. The Coulomb correlation and spin-orbit coupling play important role in deciding the…
Magnetism in transition metal compounds is usually considered starting from a description of isolated ions, as exact as possible, and treating their (exchange) interaction at a later stage. We show that this standard approach may break down…
Charge carrier concentrations in acceptor-doped proton-conducting perovskites are to a large extent determined by the hydration and oxidation of oxygen vacancies, which introduce protons and holes, respectively. First-principles modeling of…
Double perovskite compounds containing 5d transition metal elements have been extensively studied as platforms for multipolar order phenomena stemming from spin-orbit-entangled 5d electrons. In this study, we examine the interplay between…
Transport and magnetic properties along with high resolution valence band photoemission study of disordered double perovskite Sr$_{2}$TiIrO$_{6}$ has been investigated. Insulator to insulator transition along with a magnetic transition…
The choice that a solid system "makes" when adopting a crystal structure (stable or metastable) is ultimately governed by the interactions between electrons forming chemical bonds. By analyzing 6 prototypical binary transition-metal…
By means of first-principles density-functional theory (DFT) calculations, we perform a comparative analysis of the electronic and magnetic properties of transition metal-doped TiO$_2$. The electronic band gaps of Ti$_x$M$_{1-x}$O$_2$,…
We consider strongly spin-orbit coupled double perovskites A$_2$BB'O$_6$ with B' magnetic ions in either $d^1$ or $d^2$ electronic configuration and non-magnetic B ions. We provide insights into several experimental puzzles, such as the…
Organo-metallic molecular structures where a single metallic atom is embedded in the organic backbone are ideal systems to study the effect of strong correlations on their electronic structure. In this work we calculate the electronic and…
Three-dimensional metal halide double perovskites such as Cs$_2$AgBiBr$_6$ exhibit pronounced excitonic effects due to their anisotropic electronic structure and chemical localization effects. Their two-dimensional derivatives, formed by…
A short introduction to the complex phenomena encountered in transition metal oxides with either charge or orbital or joint charge-and-orbital order, usually accompanied by magnetic order, is presented. It is argued that all the types of…