Related papers: Optical Properties and Correlation Effects in NaxC…

We present results of studies of charge disproportionation (CD) and spin differentiation in Na$_x$CoO$_2$ using the correlated band theory approach (local-density approximation+Hubbard U:LDA+U). The simultaneous CD and gap opening can be…

Millimeter-sized single crystals of LaFeAsO were grown from NaAs flux and the in-plane optical properties were studied over a wide frequency range. A sizable electronic correlation effect was indicated from the analysis of the free-carrier…

In this work, we have simulated the processes of broadening the first exciton band in optical absorption spectra (OA) for InP/ZnS ensembles of colloidal quantum dots (QDs). A phenomenological model has been proposed that takes into account…

Sodium cobaltate Na_xCoO_2 as dopable strongly correlated layered material with a triangular sublattice still poses a challenging problem in condensed matter. The intriguing interplay between lattice, charge, spin and orbital degrees of…

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…

Charge disproportionation (CD) and spin differentiation in Na$_{1/2}$CoO$_2$ are studied using the correlated band theory approach. The simultaneous CD and gap opening seen previously is followed through a first order charge…

Motivated by the newly discovered Co-based superconductor Na2CoSe2O, we performed systematic calculations of its electronic band structures using the density functional theory (DFT) plus the dynamical mean-field theory (DMFT) approaches.…

We report a comprehensive Cu $K$-edge RIXS investigation of $\rm La_{2-x}Sr_xCuO_4$ (LSCO) for 0$\leq$x$\leq$0.35, stripe-ordered $\rm La_{1.875}Ba_{0.125}CuO_4$ (LBCO), and $\rm La_{2}Cu_{0.96}Ni_{0.04}O_4$ (LCNO) crystals. The RIXS…

We performed a neutron-scattering experiment to investigate the effect of distortion of CuO2 planes on the low-energy spin correlation of La1.94-xSrxCe0.06CuO4 (LSCCO). Due to the carrier-compensation effect by co-doping of Sr and Ce, LSCCO…

Raman scattering experiments on Na_{x}CoO_2 yH_2O single crystals show a broad electronic continuum with a pronounced peak around 100 cm-1 and a cutoff at approximately 560 cm-1over a wide range of doping levels. The electronic Raman…

The presence of complexity in the electronic structure of strongly correlated electron system NdCoO$_3$ (NCO) have sparked interest in the investigation of its physical properties. Here, we study the the Seebeck coefficient ($\alpha $) of…

We investigate the excitation spectrum of strongly correlated sodium cobaltate within a realistic many-body description beyond dynamical mean-field theory (DMFT). At lower doping around $x$=0.3, rather close to Mott-critical half-filling,…

We obtain the electronic states and structures of two-dimensional cobalt oxides, Na$_{x}$CoO$_{2}$ (x=0, 0.35, 0.5 and 0.75) by utilizing the full-potential linear muffin-tin orbitals (FP-LMTO) methods, from which some essential electronic…

Previous ARPES experiments in NaxCoO2 reported both a strongly renormalized bandwidth near the Fermi level and moderately renormalized Fermi velocities, leaving it unclear whether the correlations are weak or strong and how they could be…

Non-Common Path Aberrations (NCPA) are one of the main limitations for extreme Adaptive Optics (AO) system. NCPA prevent extreme AO systems to achieve their ultimate performance. These static aberrations are unseen by the wave front sensor…

We investigated optical absorption coefficient spectra of an epitaxial VO2 film in wide photon energy (0.5 - 5.0 eV) and temperature (100 - 380 K) regions. In its insulating phase, we observed two d-d transition peaks around 1.3 eV and 2.7…

ZnO is co-doped with Na+ and Si4+ in the ratio 2:1. The ratio was intentionally chosen so that net valence state of dopant theoretically matches that of host. This is to avoid dependence in the amount of oxygen vacancies/interstitials…

Motivated by recent experiments and band calculation results, we investigate the possibility of superconductivity originating from the $a_{1g}$ band of Na$_x$CoO$_2\cdot y$H$_2$O assuming the absence of $e_g'$ pockets. We adopt a single…

To shed light on the symmetry of the superconducting order parameter in Na_xCoO_2-yH_2O, the Mn doping effects are studied. X-ray absorption spectroscopy verifies that the doped Mn impurities occupy the Co sites and are with a valance close…

Context. Spectroscopy of exoplanets is very challenging because of the high star-planet contrast. A technical difficulty in the design of imaging instruments is the noncommon path aberrations (NCPAs) between the adaptive optics (AO) sensing…