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The continuous time random walk approach for hopping conduction in disordered systems is modified to obtain accurate DC conductivity values over a wide range of hopping site densities. The modification involves eliminating a small fraction of particularly ...
We have constructed maximally localized Wannier functions for prototype structures of solid molecular hydrogen under pressure, starting from local-density approximation and tight-binding Bloch wave functions. Each occupied Wannier function can be associate ...
We present comparisons of theoretical and simulation results for static and dynamical correlation functions for a very simple model of attractive colloidal systems, the short-ranged square-well potential. In the region of the phase diagram investigated, th ...
High-resolution angle-resolved photoemission data show that a metal-insulator Mott transition occurs at the surface of the quasi-two-dimensional compound 1T-TaSe2. The transition is driven by the narrowing of the Ta 5d band induced by a temperature-depende ...
Differences and analogies between disorder-induced localization and electric-field-induced localization are discussed. Calculations using a tight binding model and transfer matrix method for disordered superlattices are reported. Our results indicate the e ...
Resonant inelastic x-ray scattering (RIXS) yields clear evidence of spectroscopic Kondo scales in heavy fermions. In YbInCu4 and YbAgCu4 RIXS probes the Yb2+ component of the hybrid ground state and the temperature dependence of the Yb 4f occupation. We re ...
We used thermal neutron irradiation to produce disorder in Bi-2212 single crystals (T-c = 85 K), at a constant carrier density. The irradiated samples were insulators. High-temperature superconductivity with a lower T-c than prior to irradiation could be r ...
Optical and photoemission experiments reveal unexpected spectral signatures of one-dimensional band insulators. In the model compound (NbSe4)(3)I the optical conductivity decays as a power law sigma(1)(omega) similar to omega(-4.25) above a sharp gap edge. ...
Neutral and anionic Cu-n clusters (Cu-2, Cu-3, Cu-6 and Cu-7(-)) are studied within density functional theory via the local density approximation (LDA) and the generalized-gradient approximation (GGA) of Perdew and Wang for exchange and correlation. Three ...
A dynamical theory of multiphoton transitions in semiconductors is developed using a density matrix approach. It is shown that, in dipole approximation, these transitions require a mixed parity of the basis stales and that band-diagonal coupling's of the e ...
