Gain of intersubband Raman lasing in modulation-doped asymmetric coupled double quantum wells

A microscopic theory is developed for the laser gain due to stimulated intersubband electronic Raman effect pumped by CO2 laser in modulation-doped asymmetric coupled double quantum wells. We focus on the charge density excitation mechanism for electronic Raman scattering, taking into account the coupling between intersubband plasmons and LO phonons. Numerical simulations for the temporal variation of stimulated Stokes photon density, subband populations and output Raman laser power are carried out by using the self-consistent conventional rate equations with stimulated Raman gain coefficient.