Related papers: DFT+U simulation of the Ti${}_4$O${}_7$-TiO${}_2$ …
Intriguingly conducting perovskite interfaces between ordinary band insulators are widely explored, whereas similar interfaces with Mott insulators are still not quite understood. Here we address the (001), (110), and (111) interfaces…
We study the chemical nature of the bonding of an oxide layer to the parent metal. In order to disentangle chemical effects from strain/misfit, Ti(10$\bar{1}$0)/TiO$_{2}$(100) interface has been chosen. We use the density functional…
To resolve the microscopic origin of magnetism in the Fe2O3/FeTiO3-system, we have performed density functional theory calculations taking into account on-site Coulomb repulsion. By varying systematically the concentration, distribution and…
By means of first-principles density-functional theory (DFT) calculations, we perform a comparative analysis of the electronic and magnetic properties of transition metal-doped TiO$_2$. The electronic band gaps of Ti$_x$M$_{1-x}$O$_2$,…
The 2-dimensional electron system at the interface between LaAlO$_{3}$ and SrTiO$_{3}$ has several unique properties that can be tuned by an externally applied gate voltage. In this work, we show that this gate-tunability extends to the…
We have measured photoemission spectra of two kinds of TiO$_2$-capped VO$_2$ thin films, namely, that with rutile-type TiO$_2$ (r-TiO$_2$/VO$_2$) and that with amorphous TiO$_2$ (a-TiO$_2$/VO$_2$) capping layers. Below the Metal-insulator…
Understanding the mechanism of the heterojunction is an important step towards controllable and tunable interfaces for photocatalytic and photovoltaic based devices. To this aim, we propose a thorough study of a double heterostructure…
Emergent phases in the two-dimensional electron gas (2DEG) formed at the interface between two insulating oxides have attracted great attention in the past decade. We present ab-initio electronic structure calculations for the interface…
We present an ab initio study of the (001) interfaces between two insulating perovskites, the polar LaAlO3 and the nonpolar SrTiO3. We observe an insulating-to-metallic transition above a critical LaAlO3 thickness. We explain that the high…
We use density functional theory plus dynamical mean-field theory to demonstrate the emergence of a metallic layer at the interface between the two Mott insulators LaTiO$_3$ and LaVO$_3$. The metallic layer is due to charge transfer across…
We report the formation of a non-magnetic band insulator at the isopolar interface between the antiferromagnetic Mott-Hubbard insulator LaTiO3 and the antiferromagnetic charge transfer insulator LaFeO3. By density functional theory…
The deposition of a thin oxide layer at metal/semiconductor interfaces has been previously reported as a means of reducing contact resistance in 2D electronics. Using X-ray photoelectron spectroscopy with in-situ Ti deposition, we fabricate…
We have studied the transport properties of LaTiO3/SrTiO3 (LTO/STO) heterostructures. In spite of 2D growth observed in reflection high energy electron diffraction, Transmission Electron Microscopy images revealed that the samples tend to…
A phenomenological model for the interface between trivial and topological two-dimensional insulators possessing the same band gap is presented. The model depends on three measurable parameters, the energy gap $E_g$, the Fermi velocity of…
We propose a simple analytical model to explain possible appearance of the metallic conductivity in the two-dimensional (2D) LaAlO$_3$/SrTiO$_3$ interface. Our model considers the interface within a macroscopic approach which is usual to…
Systematic investigation of atomic structure of N-ion implanted TiO2 (thin films and bulk ceramics) was performed by XPS measurements (core levels and valence bands) and first-principles density functional theory (DFT) calculations. In bulk…
We report on a metal-insulator transition in the LaAlO3-SrTiO3 interface electron system, of which the carrier density is tuned by an electric gate field. Below a critical carrier density n_c ranging from 0.5-1.5 * 10^13/cm^2, LaAlO3-SrTiO3…
Titanium dioxide (TiO2) is a wide band gap semiconducting material which is promising for photocatalysis. Here we present first-principles calculations to study the pressure dependence of structural and electronic properties of two TiO2…
Resistive switching devices herald a transformative technology for memory and computation, offering considerable advantages in performance and energy efficiency. Here we employ a simple and scalable material system of conductive oxide…
The conducting quasi-two dimensional electron system (q2DES) formed at the interface between LaAlO3 and SrTiO3 band insulators is confronting the condensed matter physics community with new paradigms. While the mechanism for the formation…