Self-consistent analysis of carrier-transport and carrier-capture dynamicsin quantum cascade intersubband semiconductor lasers

A methodology for the self-consistent analysis of carrier transport and car rier capture aspects of the dynamics of quantum cascade intersubband semico nductor lasers is described in this paper. The approach is used to analyze two prototype quantum cascade lasers, The self-consistent analysis incorpor ates the calculation of the electron densities and temperatures in each sub band, together with the intersubband relaxation time. In the calculation of the relaxation time, we take into account the electron interaction with po lar optical and acoustic phonons, as well as electron degeneracy. In additi on, we also calculate the capture time, considering backward processes that play a role in the electron transition from an injection into an active re gion. The calculations indicate intersubband relaxation times of order 1 ps and capture times of order 100 fs.