Related papers: Multiple-source optical spectral weight transfer i…
We present an optical spectroscopy study on singe crystalline ErTe$_3$, a rare-earth-element tri-telluride which experiences two successive charge density wave (CDW) transitions at T$_{c1}$ = 267 K and T$_{c2}$ = 150 K. Two corresponding…
We use low energy optical spectroscopy and first principles LDA+DMFT calculations to test the hypothesis that the anomalous transport properties of strongly correlated metals originate in the strong temperature dependence of their…
We report the temperature- and magnetic-field-dependent optical conductivity spectra of the heavy electron metal YbIr$_2$Si$_2$. Upon cooling below the Kondo temperature ($T_{\rm K}$), we observed a typical charge dynamics that is expected…
We present experimental results on the optical absorption spectra of epitaxial graphene from the visible to the terahertz (THz) frequency range. In the THz range, the absorption is dominated by intraband processes with a frequency…
The spectral weight (SW) for optical transitions in FeSi and MnSi are calculated as function of temperature by means of LMTO-LDA band calculations. The main effects, caused by structural disorder and electronic Fermi-Dirac distribution, act…
We present the in-plane optical reflectance measurement on single crystals of URu$_2$As$_2$. The study revealed a strong temperature-dependent spectral evolution. Above 50 K, the low frequency optical conductivity is rather flat without a…
We report a series of measurements of the effect of an electric field on the frequency of the ultranarrow linewidth $^7F_0 \rightarrow$ $^5D_0$ optical transition of $\rm Eu^{3+}$ ions in an $\rm Y_2SiO_5$ matrix at cryogenic temperatures.…
We investigated excitation spectra of the one-dimensional chain compound Sr$_{2}$CuO$_{3}$. The small peak at 2.3 eV in the loss function was turned to correspond to the strong charge transfer transition at 1.8 eV in conductivity. It has…
We have measured the electrodynamic response in the metallic state of three highly anisotropic conductors, (TMTSF)_2 X, where X=PF_6, AsF_6, or ClO_4, and TMTSF is the organic molecule tetramethyltetraselenofulvalene. In all three cases we…
Ab initio calculations and angle-resolved photoemission experiments show that the bulk and surface electronic structure of Weyl semimetal candidate MoTe$_2$ changes significantly by tuning the chemical potential by less than 0.4 eV.…
We report on a systematic optical investigation of w\"ustite. In addition, the sample under consideration, Fe0.93O, has been characterized in detail by electrical transport, dielectric, magnetic and thermodynamic measurements. From infrared…
A method to analyze optical transitions is developed by combining the Kubo-Greenwood formula with the unfolding method to construct an unfolded electronic band structure with optical transition weights, which allows us to investigate how…
The optical response of the two-band superconductor MgB$_2$ has been studied in the 0.7-4 THz range on films with very low impurity level. The effect of the high-energy $\sigma$-gap is observed in the ratio $R_S/R_N$ between the normal and…
The angle-resolved photoemission spectrum of the organic conductor TTF-TCNQ exhibits an unusual transfer of spectral weight over a wide energy range for temperatures 60K<T<260K. In order to investigate the origin of this finding, here we…
The absolute value of the electrical conductivity sigma of elemental metals even at the room temperature range is not well theoretically understood. This is particularly true in multivalent metals. This paper empirically found that…
The negative thermal expansion (NTE) effect has been found generally combined with structural phase transitions. However, the charge and orbital freedoms of the NTE has not been well studied. This study employs angle-resolved photoemission…
Flatband systems form a new class of materials that challenge the conventional wisdom of transport. The intrinsically strong electronic correlations combined with the vanishing kinetic energy scale suggest a sensitive dependence of…
Superconducting EuFe2(As0.82P0.18)2 single crystals are investigated by infrared spectroscopy in a wide frequency range. Below Tc=28K a superconducting gap forms at 2\Delta_{0} = 9.5 meV = 3.8 k_B T_c causing the reflectivity to sharply…
We numerically study optical conductivity $\sigma (\omega )$ near the "antiferromagnetic" phase transition in the square-lattice Hubbard model at half filling. We use a cluster dynamical mean field theory and calculate conductivity…
The effect of intermolecular interactions on intensity redistribution between individual electronic transitions in different polymorphs of fluorene and dibenzofuran was studied by transmittance electronic spectroscopy in the energy range…