Related papers: Coherent and incoherent bands in La and Rh doped S…
Electronic structure calculations indicate that the Sr2FeSbO6 double perovskite has a flat-band set just above the Fermi level that includes contributions from ordinary sub-bands with weak kinetic electron hopping plus a flat sub-band that…
We have performed photoemission and soft x-ray absorption studies of pyrochlore-type Ru oxides, namely, the filling-control system Sm$_{2-x}$Ca$_x$Ru$_2$O$_7$ and the bandwidth-control system Sm$_{2-x}$Bi$_x$Ru$_2$O$_7$, which show…
Using angle-resolved photoemission spectroscopy, we studied the electronic structure of NaFe$_{1-x}$Co$_x$As from an optimally doped superconducting compound ($x=0.028$) to a heavily overdoped non-superconducting one ($x=0.109$). Similar to…
The band structures of pure and hole doped La$_2$CuO$_4$ with antiferromagnetic (AFM) spin-fluctuations are calculated and compared to spectral weights of ARPES. It is shown that observations of coexisting Fermi surface (FS) arcs and closed…
The electronic structure of the reentrant superconductor Eu(Fe$_{0.86}$Ir$_{0.14}$)$_{2}$As$_{2}$ (T$_c$ = 22 K) with coexisting ferromagnetic order (T$_M$ = 18 K) is investigated using angle-resolved photoemission spectroscopy (ARPES) and…
We investigate the electronic correlation effects in La$_{2.85}$Pr$_{0.15}$Ni$_2$O$_7$ film grown on SrLaAlO$_4$ by fluctuation-exchange approximation. The $\gamma$ and $\delta$ bands are found to shift down with correlation while their…
The insulator to metal transition in LaTiO_3 induced by La substitution via Sr is studied within multi-band exact diagonalization dynamical mean field theory at finite temperatures. It is shown that weak hole doping triggers a large…
The experimental Mn K-edge x-ray absorption spectra of La$_{1-x}$Sr$_x$MnO$_{3}$, $x$ = 0 - 0.7 are compared with the band structure calculations using spin polarized density functional theory. It is explicitly shown that there is a…
We employ angle-resolved photoemission spectroscopy (ARPES) to investigate the electronic structures of two rotational variants of epitaxial, single-layer graphene on Ir(111). As grown, the more-abundant R0 variant is nearly charge-neutral,…
High-$T_c$ superconductivity (SC) was recently found in the bilayer material La$_3$Ni$_2$O$_7$ (La327) under high pressures. We study the bilayer two-orbital Hubbard model derived from the band structure of the La327. The model is solved by…
We have performed an in situ angle-resolved photoemission spectroscopy (ARPES) on single-crystal surfaces of La$_{0.6}$Sr$_{0.4}$MnO$_{3}$ (LSMO) thin films grown on SrTiO$_{3}$ (001) substrates by laser molecular beam epitaxy, and…
The substitutional dependence of valence and spin-state configurations of Sr(Fe$_{1-x}$Co$_x$)$_2$As$_2$ ($x =$ 0, 0.05, 0.11, 0.17, and 0.38) is investigated with near-edge x-ray absorption fine structure at the $L_{2,3}$ edges of Fe, Co,…
We present detailed LDA'+DMFT investigation of doping dependence of correlation effects in novel K{1-x}Fe{2-y}Se2 superconductor. Calculations were performed at four different hole doping levels, starting from hypothetical stoichiometric…
Among numerous hypotheses, recently proposed to explain superconductivity in iron-based superconductors [1-9], many consider Fermi surface (FS) nesting [2, 4, 8, 10] and dimensionality [4, 9] as important contributors. Precise determination…
Polarization-controlled synchrotron radiation was used to map the electronic structure of buried conducting interfaces of LaAlO$_3$/SrTiO$_3$ in a resonant angle-resolved photoemission experiment. A strong dependence on the light…
Superconductivity frequently appears by doping compounds that show a collective phase transition. So far, however, this has not been observed in topological materials. Here we report the discovery of superconductivity induced by Ga doping…
Experimental and theoretical studies on superconductivity in SrIr$_2$ and SrRh$_2$ Laves phases are presented. The measured resistivity, heat capacity, and magnetic susceptibility confirm the superconductivity of these compounds with $T_c$…
Recent results on electrons and holes doped CuO 2 planes confirm the marked covalency of CuO bonding, suggesting a band picture of long and short range antiferromagnetism. The maxima of superconductive T c versus doping can be related to…
Based on the possible superconducting (SC) pairing symmetries recently proposed, the quasiparticle interference (QPI) patterns in electron- and hole-doped Sr$_{2}$IrO$_{4}$ are theoretically investigated. In the electron-doped case, the QPI…
We report photoemission studies of polycrystalline samples of Sr-doped GdTiO_{3+delta}, which undergoes a Mott-Hubbard-like metal-insulator transition at a Ti-concentration of about 20%. The Ti 3d-derived valence band near the Fermi level…