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Dynamical Mean-Field Theory for Doped Antiferromagnets

We have generalized the dynamical mean-field theory to study the doping dependence of the crossover from antiferromagnetic to short-range order modeled by an incommensurate spin density wave in the Hubbard model. The local self-energy which includes spin fluctuations gives quasiparticle weights and spectral properties in good agreement with quantum Monte Carlo and exact diagonalization data in two

Transient Electromagnetic Wave Propagation in Transverse Periodic Media

In this paper, wave propagation of electromagnetic pulses in media that are periodic in one spatial direction is analyzed by a time domain technique. The special case of wave propagation in an inhomogeneous planar waveguide with perfectly conducting walls is also discussed. The wave equation is reduced to a set of one dimensional first order hyperbolic equations by an expansion in a complete set o

Picosecond X-ray Diffraction Studies of Bulk and Nanostructure Materials

Popular Abstract in Swedish Snabba fenomen, som inträffar efter laserexcitation, har studerats med tidsupplöst röntgendiffraktion (TXRD). I de flesta experimenten har en ljuspuls från en femtosekundlaser använts för att excitera provet, och dynamiken har undersökts med röntgenljus. Tidsupplösta röntgendiffraktionsmätningar har utförts för att studera fasta halvledarmaterial, vätskor, ferro-elektriFast phenomena occurring after laser excitation were studied using time-resolved X-ray diffraction (TXRD). In most experiments, a femtosecond laser pulse was used to excite the sample, and X-rays were used as a probe. The X-ray diffraction technique was used to study bulk semiconductor samples, molten liquids, ferro-electric domain switching in potassium dihydrogen phosphate (KDP), and strain prop