in order to study some theories about nonsuperconductivity of prba2cu3o7, based on the density functional theory and with apw+lo/lapw method some calculations for prba2cu3o7 (pr123) and yba2cu3o7 (y123) were performed. the lsda+u approximation was used for pr(4f) orbitals and the effect of changing upr on the band structure, pr(4f)-dos, distribution of electrons on the planes and chains, and pr...

Orthonormal M-band wavelet bases have been constructed and applied by several authors. This paper makes three main contributions. First, it generalizes the minimal length Kregular 2-band wavelets of Daubechies to the M-band case by deriving explicit formulas for K-regular M-band scaling filters. Several equivalent characterizations of K-regularity are given and their significance explained. Sec...

An intermediate-bandwidth theory of charge-carrier mobility is developed with a focus on finite-band effects and scattering by phonons. Wide-band behavior is recovered as a limit. Two applications of the finite-band theory are discussed: in one a dip is predicted in the temperature dependence of the mobility, and in the other recently reported observations on ultrapure organic crystals are addr...

A model for high temperature superconductors based on the idea of Cooper pairs comprised of electrons from different bands is studied. We propose that the two bands relevant for the cuprates are comprised of Cu dx2−y2, dz2 , planar O pσ, and apical O pz orbitals. Along the diagonal, kx = ky in the Brillouin zone, the two band Fermi surfaces may cross. We associate the optimal doping for the hig...

We use the Gutzwiller variational theory to calculate the ground-state phase diagram and quasiparticle bands of LaOFeAs. The Fe3d-As4p Wannier-orbital basis obtained from density-functional theory defines the band part of our eight-band Hubbard model. The full atomic interaction between the electrons in the iron orbitals is parametrized by the Hubbard interaction U and an average Hund's-rule in...

Multidimensional spatiotemporal parametric ‘‘simultons’’ ~simultaneous solitary waves! are possible in a nonlinear x (2) medium with a Bragg grating structure, where large effective dispersion occurs near two resonant band gaps for the carrier and second-harmonic field, respectively. The enhanced dispersion allows much reduced interaction lengths, as compared to bulk medium parametric simultons...

A fracture theory for a heterogeneous aggregate material which exhibits a gradual strainsoftening due to microcracking and contains aggregate pieces that are not necessarily small compared to struttural dimensions is developed. Only Mode I is considered. The fracture is modeled as a blunt smeared crack band, which is justified by the random nature of the microstructure. Simple triaxial stress-s...

We isolate logarithmic divergences from bosonic string amplitudes on a disc. These divergences are compared with ‘tadpole’ divergences in the effective field u theory with a cosmological term, which also contains an effective potential for the dilaton. Also, corrections to p-functions are compared with variations of the effective action. In both cases we find an inconsistency between the two. T...

In present work, we have calculated the electronic properties including density of states and electron density for GaN, InN and InxGa1-xN  in wurtzite phase for x=0.5. The study is based on density functional theory with full potential linearized augmented plane wave method by generalized gradient approximation for calculating electronic properties. In this report we concluded that InxGa1-xN ba...