Theoretical ideas and experimental results concerning high-temperature superconductors
are reviewed. Special emphasis is given to calculations performed with the help of …

The authors review the results of a wide variety of experiments on materials such as La 2
CuO 4 and Nd 2 CuO 4 that contain weakly coupled CuO 2 layers. These materials are …

A systematic study of optical and transport properties of the Hubbard model, based on the
Metzner-Vollhardt dynamical mean-field approximation, is reviewed. This model shows …

Cooperative properties of self-localized carriers on a lattice are discussed and reviewed at a
fairly basic level with an emphasis on developments of the strong-coupling theory of …

Optical and Raman-scattering studies of a-, b-, and c-axis YBa 2 Cu 3 O 6+ x between 0.025
and 5.5 eV are presented as a function of doping, and compared to the results of Bi 2 Sr 2 …

We perform the exact diagonalization of two, four, and six vibrating molecules strongly
coupled with one electron to show that a small polaron describes both adiabatic and …

The possibility of polaron formation within a model of local electron-phonon interactions is
considered. It is shown that, unlike the continuous limit, the solution to the Schrodinger …

Written by eminent researchers in the field, this text describes the theory of superconductivity
and superfluidity starting from liquid helium and a charged Bose-gas. It also discusses the …

The low-energy electronic states in La 2− x Sr x CuO 4 have recently been probed by soft-x-
ray-absorption measurements as a function of doping (x) from the insulating well into the …

The photoconductivity, σ ph (ω), and the optical conductivity, σ (ω), of lightly-doped single
crystals of Nd 2 CuO 4− δ are compared over the photon energy range 0.6< h ̵ ω< 3 eV …