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We have directly measured the carrier temperature in semiconductor optical amplifiers (SOAs) via spontaneous emission and we demonstrate an unexpectedly high carrier temperature. The direct correlation of the temperature increase with the carrier density s ...
We present an overview of recent selective photoluminescence (PL) experiments on shallow levels in ZnSe and GaN. Through two electron transitions (TET) and electronic Raman scattering (ERS) investigations on solid phase recrystallized bulk ZnSe doped with ...
Using a differential transmission pump-probe experiment in heterodyne detection, the ultrafast gain and refractive-index dynamics of the ground-state transition in InAs/GaAs quantum-dot amplifiers emitting near 1.3 mu m at working condition, that is at roo ...
We discuss the temperature dependence of various photoluminescence transitions observed in undoped and doped GaN in the 9 to 300 K range. Samples grown using different techniques have been assessed. The mechanism underlying the various quenching behaviors ...
This thesis presents the coherence properties of polaritons in semiconductor microcavities. Semiconductor microcavities are microstructures in which the exciton ground state of a semiconductor quantum well is coupled to a photonic mode of a microresonator. ...
This work contains a theoretical analysis of the optical properties of semiconductor quantum wells embedded in planar Fabry-Perot microcavities. In particular, the properties of the system in correspondence to the excitonic transition are studied by means ...
Photoluminescence of p-type modulation doped (Cd,Mn)Te quantum wells is studied with carrier density up to 5 X 10(11) cm(-2) at various spin splittings. This splitting can be made larger than the characteristic energies of the system thanks to the giant Ze ...
Silicon has become the most important material for the semiconductor industry, due to several advantages like good heat conductance or the high quality of its oxide. Nevertheless, for opto-electronic devices, the limitation of its indirect band-gap has ant ...
We report on carrier-induced effects on emission and absorption in forward biased GaAs/AlGaAs V-groove quantum wire (QWR) diodes observed using low-temperature (10 K) photoluminescence (PL), electroluminescence (EL) and PL excitation (PLE) spectroscopy. In ...
Selective photoluminescence experiments have been used to analyse the neutral donor bound exciton spectra in n type wurtzite GaN epitaxial layers deposited on 6H-SiC, Al2O3 and GaN substrates, In heterostructure layers, the existence of residual strain dis ...