Gd. Sanders et al., CARRIER-GAIN DYNAMICS IN INXGA1-XAS ALYGA1-YAS STRAINED-LAYER SINGLE-QUANTUM-WELL DIODE-LASERS - COMPARISON OF THEORY AND EXPERIMENT/, Physical review. B, Condensed matter, 50(12), 1994, pp. 8539-8558
We present measurements and calculations of femtosecond gain dynamics
in InxGa1-xAs/AlyGa1-yAs strained-layer single-quantum-well diode lase
rs using a multiple-wavelength pump-probe technique. To aid in the int
erpretation of gain dynamics induced by both interband absorption and
stimulated emission of photons, we develop a detailed theoretical mode
l for gain dynamics in quantum-well laser diode structures and compare
it with experimental measurements. In the model, transient gain and d
ifferential transmission are computed in a multiband effective-mass mo
del including biaxial strain, valence subband mixing, and polar-optica
l-phonon scattering both within and between subbands. Transient photog
eneration of electron-hole pairs by the pump pulse and subsequent rela
xation of carriers by polar-optical-phonon scattering are calculated i
n a Boltzmann-equation framework.