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The partition function of the Hubbard model with local attraction and long-range Coulomb repulsion between electrons is written as a functional integral with an action A involving a pairing field Δ and a local potential V. After integration over V and over ...
We present second-harmonic generation experiments in p-doped asymmetrically stepped quantum wells using the emission of a free-electron laser in the wavelength interval between 13 and 18 mu m. The wells are designed such that the three fewest valence-subba ...
We report the optical properties of high quality V-groove GaAs/Al0.3Ga0.7.As quantum wires (QWRs) with different thicknesses of the GaAs layer. The systematic investigation of photoluminescence (PL) and photoluminescence excitation (PLE) spectra as a funct ...
Using femtosecond resonant luminescence, we have measured the intersubband scattering fare of electrons in wide GaAs quantum wells at very low excitation densities. Even when the spacing between the first two electron subbands is smaller than the LO phonon ...
A study of the elastic exciton-exciton Coulomb scattering in a semiconductor quantum well is presented, including the interexciton exchange of carriers and the spin degrees of freedom. The theoretical results show that electron-electron and hole-hole excha ...
Summary form only given. Radiative coupling between one or more quantum wells (QWs) and the single-cavity mode of a moderate reflectivity semiconductor microcavity leads to normal-mode coupling (NMC), observed as a doubled-peaked spectrum in reflection, tr ...
1998 Technical Digest Series Vol.7 (IEEE Cat. No.98CH36236). Opt. Soc. America Washington DC USA1998
Semiconductor quantum wires (QWRs) are promising structures for optoelectronics applications, since they can provide quantum confinement for charge carriers in two dimensions. The advantage that they offer over conventional quantum wells (QWs) is due to th ...
We report evidence of a large blue shift (up to 70 meV) in the photoluminescence spectra of InAs/InP island like quantum wells following the reduction of the InP top barrier layer thickness from 6 nm to near zero. The photoluminescence intensity only start ...
The optical properties of high-quality V-groove GaAs/AlxGa1-xAs quantum wires have been investigated using low-temperature photoluminescence (PL) and photoluminescence excitation (PLE) techniques. We systematically study the evolution of PL and PLE spectra ...
We show that the two-dimensional quantum confined Stark effect in a semiconductor quantum wire can display novel behaviour, i.e. wave function splitting and cascading. No analog to these phenomena can be found in bulk material or quantum wells. The consequ ...