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Ammonia is used for growing undoped GaN layers by gas source molecular-beam epitaxy on c-plane sapphire substrates. The growth mode is layer by layer as shown by the observation of reflection high-energy electron diffraction intensity oscillations. The str ...
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 report a comparative study by luminescence and reflectivity of GaN grown on sapphire by MOVPE, HVPE and GSMBE. Whatever the growth technique, undoped GaN shows well resolved reflectivity spectra, allowing hetero-epitaxial strain to be taken into account ...
We report on microscopic photoluminescence and photoluminescence excitation of thin Al0.3Ga0.7As/GaAs quantum wells grown on exactly oriented (001) GaAs substrates. The experiments are done at low temperature by selectively exciting a few mu m(2) of the sa ...
A quantum theory of quantum well polaritons in semiconductor microcavities is developed. The model takes into account the coupling between the exciton level and the structured continuum of electromagnetic modes relative to the particular geometry of the mi ...
We examine the room-temperature dispersive and non-dispersive cathodoluminescent (CL) signals produced by an n-InP/n(+)-InP homojunction as a function of excitation beam energy. The non-intentionally doped epilayer of the homojunction is thick enough (2.5 ...
We report on luminescence, transmission and luminescence excitation measurements on indirect-gap AlxGa1-xAs in the composition range 0.42 less than or equal to x less than or equal to 0.86. The phonon coupling strength in transitions of bound excitons is i ...
This device for measuring Brillouin scattering includes a single laser source (11), a modulator (12) placed on the path of the light emitted by the source (11) and designed to generate a pumping signal and a test signal which are injected to one end (13) o ...
Luminescence properties for C-60 single crystal, the temperature dependence of the luminescence spectra and decay kinetics were measured for a wide range of excitation energies. At low temperatures the emission spectra with well resolved structure were det ...
We calculate scattering rates of QW excitons by acoustic phonons using realistic deformation potentials for electrons and holes in structures based on GaAs. We use these rates in order to reproduce the exciton dynamics in a time-resolved photoluminescence ...
