Title :
Capture of photoexcited carriers in a single quantum well with different confinement structures
Author :
Morin, S. ; Deveaud, B. ; Clerot, F. ; Fujiwara, K. ; Mitsunaga, K.
Author_Institution :
CNET, Lannion, France
fDate :
6/1/1991 12:00:00 AM
Abstract :
The authors report experimental and theoretical studies of photoexcited carrier trapping in a GaAs/AlxGa1-xAs single quantum well with three different typical confinement layer structures: a separate-confinement heterostructure (SCH) and a graded SCH (GRIN-SCH), a linearly graded SCH (LGRIN-SCH), and a parabolically-graded SCH (PGRIN-SCH). The capture is studied by means of time-resolved luminescence with 600-fs resolution. Measurements, performed from 20 to 300 K, show an appreciably shorter trapping time in the GRIN-SCH (1 ps at 80 K to 8 ps at 300 K) than in the SCH (between 22 and 14 s in the same temperature range). Experimental results are fitted by a one-dimensional drift-diffusion model, and the mobility of holes is deduced from the calculations. A short but finite capture time at the edge of the well is demonstrated
Keywords :
III-V semiconductors; aluminium compounds; carrier lifetime; gallium arsenide; gradient index optics; luminescence of inorganic solids; photoluminescence; semiconductor quantum wells; time resolved spectra; 20 to 300 K; GRIN-SCH; GaAs-AlxGa1-xAs single quantum well; III-V semiconductors; confinement layer structures; finite capture time; graded refractive index; holes; one-dimensional drift-diffusion model; parabolically-graded SCH; photoexcited carrier trapping; separate-confinement heterostructure; temperature range; time-resolved luminescence; trapping time; Carrier confinement; Charge carrier processes; Luminescence; Optical scattering; Phonons; Quantum mechanics; Quantum well lasers; Resonance; Semiconductor lasers; Time measurement;
Journal_Title :
Quantum Electronics, IEEE Journal of
