Influence of electron–electron scattering on carrier distributions in optically pumped terahertz laser structures under short pulse excitation
An ensemble Monte Carlo method is employed to study the carrier dynamics of optically pumped 3-subband quantum-well lasers under sub-picosecond pulse excitation. The influences in time and energy domains of electron?electron scatterings (EES) toward the electron distributions on each subband, both critically important for inter-subband THz lasers, are carefully analyzed. We find that, out of three subbands, EES would affect the occupancy on the ground subband most seriously, and the upper laser subband may be influenced more easily by EES than the lower laser subband.