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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 ...
The electronic states in the conduction and valence bands of quantum wires are studied by means of the effective mass hamiltonian and the Luttinger hamiltonian. The band mixing effects due to the wire geometry are fully taken into account by an accurate fi ...
Differences and analogies between disorder-induced localization and electric-field-induced localization are discussed. Calculations using a tight binding model and transfer matrix method for disordered superlattices are reported. Our results indicate the e ...
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 ...
We have studied the luminescence of narrow quantum wires at photoexcitation densities of up to similar to 3 x 10(6) cm(-1). We show that even at these densities, which are well above the expected Mott density of 8 x 10(5) cm(-1), excitonic recombination do ...
The temperature and excitation intensity dependencies of the photoluminescence (PL) spectra of GaAs/Al0.3Ga0.7As superlattices (SL's) having randomly distributed well widths are studied. Our results indicate that the electronic properties of disordered SL' ...
We have studied the effect of valence band mixing on the optical properties of semiconductor quantum wires by analyzing the luminescence polarization. Large polarization anisotropy is observed and directly compared to the effects predicted by a k . p model ...
We investigate the exciton formation process from free carriers in a single GaAs quantum well. We focus on the formation processes assisted by emission and absorption of acoustic and optical phonons. The formation rates are evaluated and compared to the ex ...
GaN grown by three different methods (MOVPE, GSMBE and HVPE) have been studied using temperature (T) dependent reflectivity and photoluminescence (PL). Both non intentionally doped (MOVPE, GSMBE and HVPE), n- and p-doped samples (MOVPE and GSMBE) have been ...
Quantum many-body states of up to four excitons are studied in small parallelepipedal quantum dots with only two nondegenerate electronic levels in the conduction and in the valence bands. Only one type of hole is considered. We find the set of good quantu ...
