A K-CENTER-DOT-P MODEL FOR HOLE CAPTURE INTO A QUANTUM-WELL

A k.p model for hole capture into a quantum well has been applied to the calculation of the rates for capture via phonon and alloy scattering into a 30 angstrom In0.7Ga0.3AS-InGaAsP quantum well, a system which is suitable for lasers operating at 1.55 mum. The well has three subbands, derived from the HH1, LH1 and HH2 zone centre states. Capture of holes into the HH2 subband is predicted to be dominated by polar optical phonon emission, whereas scattering into the other two bands proceeds mainly by non-polar optical phonon emission or alloy scattering. There is structure in the capture rate plotted as a function of the energy and in-plane wavevector of the incident hole, which is attributed to instances where incident holes in barrier states undergo strong transmission into the well region. Mixing between the quantum well subbands is important through the effect upon the density of final states in capture transitions, but is less significant with respect to its effect on the screening matrix elements.