Related papers: Surface Effects in Ferroelectrics: Periodic Slab C…
We report electronic structure calculations for BaTi$_2$Sb$_2$O and discuss the results in relation to the observed superconductivity of this material when hole doped with Na. The Fermi surface shows several sheets. These include a nested…
Ferroelectric polar displacements have recently been observed in conducting electron-doped BaTiO3. The co-existence of a ferroelectric phase and conductivity opens the door to new functionalities which may provide a unique route for novel…
The electronic properties of graphene on top of ferroelectric HfO$_2$ substrates in orthorhombic phase with space group Pca2$_1$ are investigated using density functional theory calculations. The space group Pca2$_1$ was recently identified…
Previously reported formulation for electrons on curved periodic surfaces is used to analyze the band structure of an electron bound on the gyroid surface (the only triply-periodic minimal surface that has screw axes). We find that an…
Ferroelectric materials embedded with dielectric inclusions offer a unique platform for exploring novel topological polar textures. Using first-principles-based atomistic simulations, we investigate the polarization behavior of a BaTiO$_3$…
Material surfaces encompass structural and chemical discontinuities that often lead to the loss of the property of interest in the so-called dead layers. It is notably problematic in nanoscale oxide electronics, where the integration of…
Using {\it ab initio} density functional theory we explore the behavior of thin layers of metallic $d^4$ SrFeO$_3$ confined between the $d^0$ dielectric SrTiO$_3$ in a superlattice geometry. We find the presence of insulating SrTiO$_3$…
We predict a mechanism of spontaneous stabilization of a uniaxial density wave in a two-dimensional metal with an isotropic Fermi surface in the presence of external magnetic field. The topological transformation of a closed Fermi surface…
We present an ab initio $GW$ self-energy calculation of the electronic structure of LaNiO$_2$. With respect to density-functional theory we find that in $GW$ the La 4$f$ states undergo an important $+$2 eV upward shift from the Fermi level,…
Density functional theory applied to a simple ionic material, MgO, is used as a model system to clarify several aspects of electronic driven mechanism to compensate for the diverging electrostatic potential in the polar structures. We…
Flexoelectric effect is the coupling between strain, polarization and their gradients, which are prominent at the nanoscale. Although this effect is important to understand nanostructures, such as domain walls in ferroelectrics, its…
The electronic band structure and Fermi surface of ZrTe_3 was precisely determined by linearly polarized angle-resolved photoelectron spectroscopy. Several bands and a large part of the Fermi surface are found to be split by 100-200 meV…
Here, our angle resolved photoemission spectroscopy experiment reveled that the surface band structure of the 1T-VSe2 host electronic states that was not predicted or probed before. Earlier claims to support charge density wave phase can be…
By using pseudopotential method with local spin density functional approximation, the electronic band structures of Na$_{x}$CoO$_{2}$ are calculated for $x=0.25$, 0.5, 0.75, and $x=1$ in the presence of the structure relaxations. As…
Polar crystals composed of charged ionic planes cannot exist in nature without acquiring surface changes to balance an ever-growing dipole. The necessary changes can manifest structurally or electronically. An electronic asymetry has long…
Time-dependent polarization relaxation behaviors induced by a depolarization field $E_{d}$ were investigated on high-quality ultrathin SrRuO$_{3}$/BaTiO$_{3}$/SrRuO$_{3}$ capacitors. The $E_d$ values were determined experimentally from an…
The unoccupied electronic states of LaCoO$_3$ and PrCoO$_3$ are studied using room temperature inverse photoemission spectroscopy and \emph{ab initio} GGA+$\emph{U}$ band structure calculations. A fairly good agreement between experiment…
First-principles density functional calculations show that the $\textrm{SrRuO}_{3}/\textrm{PbTiO}_{3}/\textrm{SrRuO}_{3}$ multiferroic junction with asymmetric (RuO$_{2}$/PbO and TiO$_{2}$/SrO) interfaces has a large ferroelectric…
We present molecular dynamics simulations of a realistic model of an ultrathin film of BaTiO$_3$ sandwiched between short-circuited electrodes to determine and understand effects of film thickness, epitaxial strain and the nature of…
Based on First-principles calculation, we have investigated electronic structure of a ZrCuSiAs structured superconductor LaNiPO. The density of states, band structures and Fermi surfaces have been given in detail. Our results indicate that…