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We investigate a GaAs/(Ga,Al)As Fabry-Perot microcavity, into which (In,Ga)As quantum wells have been inserted. The cavity is wedge shaped, i.e., the detuning between the bare-exciton resonance and the bare optical cavity mode depends on the spatial positi ...
The most important features of the physics of microcavity-embedded quantum wells are reviewed, with particular attention to the optical properties of exciton polaritons. The strong coupling regime, in which a finite polariton mode splitting appears (also c ...
The influence of static disorder on the optical properties of microcavity-embedded quantum wells is studied by means of a microscopic model. Both the exciton-photon coupling and the exciton-disorder interaction are treated nonperturbatively. Despite the no ...
Rhombohedral Pb(Zr0.70Ti0.30)O-3 thin films of four different well-defined textures, namely, (100), (111), bimodal (110)/(111), and (100)/(111), were prepared by a sol-gel method. The films were characterized in terms of grain size, presence of second phas ...
Piezoelectric properties of Pb(Zr,Ti)O-3 thin films are investigated as a function of the number of bipolar (switching) and unipolar (nonswitching) voltage pulses. The longitudinal piezoelectric coefficient d(33) decreases with bipolar fatigue reflecting t ...
We show that the average lattice disorder in YBa2Cu3O6.9 films grown by ion-beam sputtering is homogeneous and can be quantified by introducing the lattice coherence length rc that is extracted from the width of X-ray diffraction rocking curves. The superc ...
In vitro production of tumor necrosis factor-alpha (TNF-alpha), interleukin-2 (IL-2), IL-4, IL-6, IL-10 and oligoclonal IgG (IgG OB) was evaluated in the aim to investigate their profile in correlation with multiple sclerosis (MS) clinical activity and cli ...
Identical GaAs/Al0.2Ga0.8As multiple-quantum-well (MQW) structures uniformly doped with Si at various concentrations ranging from 1x10(17) to 1X10(19) cm(-3) are grown by molecular-beam epitaxy to study the effects of the background Si-doping level on the ...
The interplay of disorder effects and exciton-exciton interactions in the four-wave-mixing process in quantum wells is investigated. Experiments are performed employing femtosecond and picosecond pulses to have either good temporal or good spectral resolut ...
We have irradiated by thermal neutrons single crystals of the Bi-2212 high T-c superconductor. The irradiated samples are insulators, but they regain high T-c superconductivity after an annealing in He at 450-550 degrees C. Depending on irradiation doses a ...
