Related papers: Ab-initio study of SrTiO3 surfaces
First-principles calculations based on density functional theory (DFT) and the pseudopotential method have been used to study the stoichiometric and reduced SnO2 (110) surface. The ionic relaxations are found to be moderate for both the…
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…
Highly-crystalline ferroelectric oxides integrated on Si hold great promise for energy-efficient memory and logic technologies. Exploiting epitaxial strain engineering in these materials is, however, severely hampered on Si, where the large…
In a common paradigm, the electronic structure of condensed matter is divided into weakly and strongly correlated compounds. While conventional band theory usually works well for the former class, many-body effects are essential for the…
The polarization response of a material to a strain gradient, known as flexoelectricity, holds great promise for novel electromechanical applications. Despite considerable recent progress, however, the effect remains poorly understood. From…
We have investigated the out-of-plane lattice relaxation related to the ferroelectric transitions in epitaxial BaTiO$_3$ (BTO) films using synchrotron X-ray diffraction. Under either compressive strain or tensile strain, there is evidence…
Structural studies on ultrathin SrRuO3/BaTiO3/SrRuO3 capacitors, with BaTiO3 thicknesses of between 5 nm and 30 nm, show well-defined interfaces between ferroelectric BaTiO3 and electrode SrRuO3 layers. In these capacitors, we cannot…
Based on recent developments in the first-principles theory of flexoelectricity, we generalize the concept of absolute deformation potential to arbitrary nonpiezoelectric insulators and deformation fields. To demonstrate our formalism, we…
We electron-dope single crystal samples of SrTiO_3 by exposing them to Ar^+ irradiation and observe carrier mobility similar in its magnitude and temperature dependence to the carrier mobility in other electron-doped SrTiO3 systems. We find…
We revisit the phase diagram of BaTiO$_3$ under biaxial strain using a first principles-based effective Hamiltonian approach. We show that, in addition to the tetragonal ($c$), quasi-rhombohedral ($r$), and quasi-orthorhombic ($aa$)…
We investigate the surface electronic structure and thermodynamic stability of the SrTiO3 (111) slabs using density functional theory. We observe that, for Ti-terminated slabs it is indeed possible to create a two-dimensional electron gas…
The electronic structure and thermodynamic stability of tetragonal $\rm{BiFeO_3}$(001) surfaces have been investigated using density functional theory. In this work, four different structures having different lattice constants with two…
We develop the multi-scale ab-initio scheme for correlated electrons (MACE) for transitionmetal-oxide heterostructures, and determine the parameters of the low-energy effective model. By separating Ti t2g bands near the Fermi level from the…
The local structural distortions in polydomain ferroelectric PbTiO3/SrTiO3 superlattices are investigated by means of high spatial and energy resolution electron energy loss spectroscopy combined with high angle annular dark field imaging.…
Charge redistribution across heterojunctions has long been utilized to induce functional response in materials systems. Here we examine how the composition of the terminating surface affects charge transfer across a heterojunction…
We have investigated electronic and magnetic properties of ultrathin SrRuO$_{3}$ (SRO) film grown on (111) SrTiO$_{3}$ substrate using the {\it ab initio} electronic structure calculations. Ru-terminated SRO (111) film suffers from strong…
An extensive theoretical investigation of the nonpolar (10$\bar{1}$0) and (11$\bar{2}$0) surfaces as well as the polar zinc terminated (0001)--Zn and oxygen terminated (000$\bar{1}$)--O surfaces of ZnO is presented. Particular attention is…
Atomically engineered oxide multilayers and superlattices display unique properties responsive to the electronic and atomic structures of the interfaces. We have followed the growth of ferroelectric BaTiO3 on SrRuO3 electrode with in situ…
First-principles density functional calculations are performed to investigate the interplay between inplane strains and interface effects in 1by1 PbTiO3/SrTiO3 and BaTiO3/SrTiO3 superlattices of tetragonal symmetry. One particular emphasis…
In this Letter we present first principle calculation of surface energies of rock-salt (B1), zinc-blende (B3), and wurtzite (B4) AlN allotropes. Out of several low-index facets, the highest energies are obtained for mono-atomic surfaces…