The essential physics of the photoluminescence of a small-polaronic solid (one in which electrons, holes and excitons all find it energetically favorable to self-trap) is described. Emphasis is placed on the dependence of the decay rates associated with the various luminescence bands on excitation energy and temperature. The results are in general accord with observations on chalcogenide glasse...

We theoretically study the conductivity in arrays of metallic grains due to the variable-range multiple cotunneling of electrons with short-range (screened) Coulomb interaction. The system is supposed to be coupled to random stray charges in the dielectric matrix that are only loosely bounded to their spatial positions by elastic forces. The flexibility of the stray charges gives rise to a pola...

We present the phase diagram and dynamical correlation functions for the Holstein-Hubbard model at half filling and at zero temperature. The calculations are based on the Dynamical Mean Field Theory. The effective impurity model is solved using Exact Diagonalization and the Numerical Renormalization Group. Excluding long-range order, we find three different paramagnetic phases, metallic, bipola...

Abstract Physics of the multiferroic interfaces is currently understood mostly within a phenomenological framework based on screening polarization field and depolarizing charges. Additional effects still unexplored are band dependence interfacial charge modulation associated changes electron-phonon interaction, coupling lattice degrees freedom. Here, heterostructures colossal-magnetoresistance ...