相关论文: Correlation and surface effects in Vanadium Oxides
The evolution of electron correlation in Sr$_{x}$Ca$_{1-x}$VO$_3$ has been studied using a combination of bulk-sensitive resonant soft x-ray emission spectroscopy (RXES), surface-sensitive photoemission spectroscopy (PES), and ab initio…
We report hard x-ray photoemission spectroscopy measurements of the electronic structure of the prototypical correlated oxide SrxCa1-xVO3. By comparing spectra recorded at different excitation energies, we show that 2.2 keV photoelectrons…
Recent photoemission spectra of the perovskite series Sr$_x$Ca$_{1-x}$VO$_3$ revealed strong modifications associated with surface contributions. To study the effect of Coulomb correlations in the bulk and at the surface the quasi-particle…
Photoemission spectra of the perovskites Ca$_x$Sr$_{1-x}$VO$_3$, Ca$_x$La$_{1-x}$VO$_3$, and SrRuO$_3$ indicate that Coulomb correlations are more pronounced at the surface than in the bulk. To investigate this effect we use the dynamical…
Vanadium sesquioxide, V2O3, boasts a rich phase diagram whose description necessitates the accounting for many-body Coulomb correlations. Spectral properties of this compound have been successfully addressed within dynamical mean field…
Ca1-xSrxVO3 is a Mott-Hubbard-type correlated electron system whose bandwidth can be varied by the V-O-V bond angle, but the actual effect of bandwidth control on the electronic structure has been controversial in previous photoemission…
The optical/infrared properties of films of vanadium dioxide (VO2) and vanadium sesquioxide (V2O3) have been investigated via ellipsometry and near-normal incidence reflectance measurements from far infrared to ultraviolet frequencies.…
We have measured soft x-ray photoemission and O 1{\it s} x-ray absorption spectra of Ca$_{1-x}$Sr$_x$RuO$_3$ thin films prepared {\it in situ}. The coherent and incoherent parts have been identified in the bulk component of the…
Transition metal oxides have been one of the central objects in the studies of electron correlation effects because of their rich variety of physical properties mainly depending on the transition metal element. On the other hand, exploiting…
We apply density functional theory and the augmented spherical wave method to analyze the electronic structure of V2O3 in the vicinity of an interface to Al2O3. The interface is modeled by a heterostructure setup of alternating vanadate and…
Element- and site-specific resonant inelastic x-ray scattering spectroscopy (RIXS) is employed to investigate electron correlation effects in {$\rm NaV_2O_5$}. In contrast to single photon techniques, RIXS at the vanadium $L_3$ edge is able…
Surface effects of a doped thin film made of a strongly correlated material are investigated both in the absence and presence of a perpendicular electric field. We use an inhomogeneous Gutzwiller approximation for a single band Hubbard…
We present atomic scale images of a V_2O_3 (0001)-surface, which show that the surface is susceptible to reconstruction by dimerization of vanadium ions. The atomic order of the surface depends sensitively on the surface preparation.…
Optical conductivity spectra of single crystals of Ca_1-xSr_xVO_3 have been studied to elucidate how the electronic behavior depends on the strength of the electron correlation without changing the nominal number of electrons per vanadium…
We study the photoemission and optical conductivity response of the strongly correlated metallic system $Ca_xSr_{1-x}VO_3$. We find that the basic features of the transfer of spectral weight in photoemission experiments and the unusual…
We use the embedding approach for a dynamical mean-field method to investigate the electronic properties of a semi-infinite two band Hubbard model at half- and quarter-filling. Two effects determine the degree of correlation at the surface:…
We present a comprehensive study of the photon energy dependence of the valence band photoemission yield in the prototype Mott-Hubbard oxide V2O3. The analysis of our experimental results, covering an extended photon energy range (20-6000…
Motivated by recent experiments realizing correlated phenomena and superconductivity in 2D van der Waals devices, we consider the general problem of whether correlation effects may be enhanced by modifying band structure while keeping a…
We report on the analysis of FM selective reflection experiments on the 6S1/2->8P3/2 transition of Cs at 388 nm, and on the measurement of the surface van der Waals interaction exerted by a sapphire interface on Cs(8P3/2). Various…
The structural and electronic properties of bulk, monolayer and ultrathin films of V$_2$O$_5$ and MoO$_3$ layered oxides have been studied with first-principles density functional theory calculations including Van der Waals dispersion…