THE EFFECTS OF STRAIN ON INTRASUBBAND SCATTERING RATES IN INP-BASED STRAINED-LAYER QUANTUM-WELL LASERS

We analyze the strain effects (both compressive and tensile) on the in trasubband scattering rates for electrons and holes in InP-based strai ned-layer quantum-well (SL-QW) lasers. Carrier-carrier and carrier-LO- phonon interactions are taken into account on an equal basis within th e fully dynamic random phase approximation for multi-subband structure s at finite temperatures. The principal influences of the strain-induc ed changes in the valence band structures on the scattering rates are discussed in terms of the changes in the valence-band density of state s and the phonon coupling with holes. We show that the hole-hole inter action plays a dominant role in determining the hole scattering rates regardless of the carrier energy. On the other hand, for electron scat tering rates, the dominant scattering mechanism Switches from electron -hole interaction to electron-electron interaction as the initial ener gy of electron increases. We also demonstrate that it is essential to take into account the mutual interactions among the individual scatter ing processes, such as carrier-carrier scattering and carrier-LO-phono n scattering, when evaluating the intrasubband scattering rates in SL- QW lasers. (C) 1994 American Institute of Physics.