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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 ...
Excitons and trions in a CdTe modulation-doped quantum well are investigated by picosecond three-pulse four-wave mixing experiments as a function of temperature in the low-density regime. We show that trions are mobile for high enough temperatures. The dif ...
The fluorescence lifetime tau and quantum yield eta(f) of isolated red polydiacetylene chains dispersed in their monomer single crystal matrix were measured between 10 and 100 K. tau increases up to 120 ps at 40 K, then rapidly decreases at higher T. eta(f ...
A reordered valence band in GaN/AlxGa1-xN quantum wells with respect to GaN epilayers has been found as a result of the observation of an enhanced g factor (g*similar to3) in magnetoluminescence spectra in fields up to 55 T. This has been caused by a rever ...
The magneto-luminescence of GaN/AlGaN quantum wells in fields up to 52 T shows a field dependence that is strongly dependent on the well width. Strong redshifts are seen for the narrowest wells that are attributed to a Zeeman splitting. This is unexpected, ...
Photoluminescence excitation (PLE) spectroscopy was carried out to investigate the excitation/emission cycle of MBE grown InGaN quantum structures. Quantum well and Stranski-Krastanov type quantum box samples were chosen that emit from blue to red. The ban ...
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 ...
Influence of hydrostatic pressure on the light emission from strained GaN/AlGaN multi-quantum-well systems has been studied, Pressure coefficients of the photoluminescence peak energies show a strong reduction with respect to that of the GaN energy ? ap an ...
Exciton reflectivity from GaN/AlxGa1-xN quantum wells (QWs) shows broad peaks that are difficult to analyze within a conventional single-free-exciton model. We have applied a new formalism that allows us to separate numerically radiative and inhomogeneous ...
The photoluminescence (PL) and PL-excitation (PLE) spectra of InyCa1-yAs/AlxGa1-xAs compressively strained V-groove quantum wires (QWR's) are compared to that of lattice-matched GaAs/AlyGa1-xAs QWR's with the same wire geometry. The PL is preferentially po ...
