Intervalley shunting of electrons in modulation-doped multiple-quantum-well structures

The dynamics of intersubband transitions in modulation-doped multiple narrow GaAs-AlxGa1-xAs quantum-well structures is investigated with Monte Carlo simulations. Two quantized polar-optical-phonon approaches are considered, slab modes and guided modes, in addition to interface modes and intervalley optical-deformation-potential scattering. We demonstrate that the nature of polar modes is of secondary importance for interpreting the experimental time constants, and that L intervalley scattering has the most significant effect on carrier relaxation.