Related papers: Interband and polaronic excitations in YTiO3 from …
We explore the effects of disordered charged defects on the electronic excitations observed in the photoemission spectra of doped transition metal oxides in the Mott insulating regime by the example of the $R_{1-x}$Ca$_x$VO$_3$ perovskites,…
The doping induced insulator-metal transition in $La_{1-x}Sr_{x}TiO_{3}$ is studied using the ab-initio LDA+DMFT method. Combining the LDA bandstructure for the actual, distorted structure found recently with multi-orbital DMFT to treat…
We study optical excitations across the Mott gap in the multi-orbital Mott-Hubbard insulators RVO3. The multi-peak structure observed in the optical conductivity can be described consistently in terms of the different 3d^3 multiplets or…
First principles calculations through density functional theory (DFT)+$U$ method were performed to assess the effect of Li interstitial doping on the optoelectronic properties of NiO and of cubic, hexagonal, and monoclinic WO$_3$. The…
High temperature superconductivity in cuprates arises from doping a parent Mott insulator by electrons or holes. A central issue is how the Mott gap evolves and the low-energy states emerge with doping. Here we report angle-resolved…
The pressure-induced changes in the optical properties of the quasi-one-dimensional conductor LaTiO$_{3.41}$ were studied by polarization-dependent mid-infrared micro-spectroscopy at room temperature. For the polarization of the incident…
A combined approach of first-principles density-functional calculations and the systematic cluster-expansion scheme is presented. The dipole, quadrupole, and Coulomb matrix elements obtained from ab initio calculations are used as an input…
We carry out a comprehensive theoretical and experimental study of charge injection in Poly(3-hexylthiophene) (P3HT) to determine the most likely scenario for metal-insulator transition in this system. We calculate the optical absorption…
We investigate the crystal structure of YTiO3 at high pressures up to 30 GPa by synchrotron x-ray powder diffraction (T = 295 K). The variation of the Ti--O bond lengths with pressure evidences a distinct change in the distortion of the…
Transition metal oxides display a great variety of quantum electronic behaviours where correlations often play an important role. The achievement of high quality epitaxial interfaces involving such materials gives a unique opportunity to…
The stability, electronic structure, optical and thermoelectric properties of Te-doped BaTiO3 are investigated by first-principal calculation based on the density functional theory and Boltzmann transport theory implemented in WIEN2K and…
Resonant optical excitation of apical oxygen vibrational modes in the normal state of underdoped YBa2Cu3O6+x induces a transient state with optical properties similar to those of the equilibrium superconducting state. Amongst these, a…
We investigate changes in the optical conductivity of doped Mott insulators by tuning ultrashort pump pulses to target either the Drude or low-energy absorption regions. Using a hole-doped two-leg Hubbard ladder and a four-leg t-J ladders,…
We studied the transmittance and reflectance of the low-dimensional Mott-Hubbard insulator TiOCl in the infrared and visible frequency range as a function of pressure. The strong suppression of the transmittance and the abrupt increase of…
The microscopic mechanism of the hydrogen-induced metal-insulator transition in SmNiO$_3$ is clarified by means of density-functional theory with the Hubbard U correction. While 100% of hydrogen doping per Ni atom has been supposed to be…
We present a theoretical analysis of intraband optical transitions from the intermediate pseudo-band of confined states to the conduction band in a finite, inhomogeneous stack of self-assembled semiconductor quantum dots. The chain is…
We investigate the influence of an unoccupied band on the transport properties of a strongly correlated electron system. For that purpose, additional orbitals are coupled to a Hubbard model via hybridization. The filling is one electron per…
The question whether excess electrons in SrTiO3 form free or trapped carriers is a crucial aspect for the electronic properties of this important material. This fundamental ambiguity prevents a consistent interpretation of the puzzling…
Many materials exhibit various types of phase transitions at different temperatures, with many also demonstrating polymorphism. Doping materials can significantly alter their conductivity. In light of this, we have investigated the…
A powerful new impurity solver is shown to permit a systematic study of the doping driven Mott transition in a one-band Hubbard model within the framework of single-site dynamical mean field theory. At small dopings and large interaction…