Simulations of a room-temperature p-i-p coherently strained Si0.5Ge0.5
/Si superlattice quantum-parallel laser diode have been made, Calculat
ions have been made of the local-in-k-space population inversion betwe
en the nonparabolic heavy-hole valence minibands, HH2 and HL1. Lasing
is at 5.4 mu m and the optical dipole matrix element is 3.7 A. Analysi
s of radiative-and-phonon scattering between the ''mixed'' bands indic
ates a lifetime difference between the upper and lower states of 2.4 p
s. At an injected current density of 5000 A/cm(2), a laser gain of 134
cm(-1) is calculated. (C) 1998 American Institute of Physics. [S0021-
8979(98)05507-8].