GaAs/AlGaAs multiple quantum wells (MQW) grown by metalorganic chemical vapor deposition have been studied. The growth conditions were tailored to optimize the nonlinear optical properties. Previous studies of the wavelength dependence of nonlinear excitonic absorption have been limited to relatively small intensities. Measurements are reported of the spectral dependence of the absorption coefficient of GaAs/AlGaAs MQWs near the n equals 1 excitonic resonances for intensities that vary by more than three orders of magnitude. Measurements were made in CW conditions, using pulses 2-ps long. The preliminary results show that picosecond pulses are 2-3 times more effective than CW excitation in saturating absorption when comparable average intensities are used. This is attributed to diffusion of photoexcited carriers out of the 15- mu m spot. Quantitative comparison of pulsed and cw spectra vs. input spot size is presented.
|Original language||English (US)|
|Title of host publication||Unknown Host Publication Title|
|Publisher||Optical Soc of America|
|Number of pages||3|
|State||Published - 1987|
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