INTERSUBBAND RELAXATION IN MODULATION-DOPED MULTIPLE-QUANTUM-WELL STRUCTURES

Photoexcited carrier behavior in modulation-doped multiple narrow GaAs-AlxGa1-xAs quantum-well structures which vary in quantum-well width and doping concentration is investigated with Monte Carlo simulations. The model includes scattering of Gamma-valley subband electrons by confined slab and interface-polar-optical phonons and between Gamma-valley and L-valley electrons via optical-deformation-potential phonons. The model closely predicts time constants for electron relaxation found experimentally and shows that the effect of including the L-valley transitions in the Monte Carlo simulation is essential.