Design and performance optimization of optically-pumped mid-infrared intersubband semiconductor lasers

We show that self-consistent simulations of asymmetric coupled double-quantum wells (ACQW) can be used efficiently to increase significantly the optical performances of optically-pumped mid-infrared intersubband semiconductor lasers by increasing the electron concentration in the quantum well. Our calculations, which account for screening effect and degenerate statistics, show optical gain in excess of 100/cm for pumping intensity of 39 kW/cm² can be achieved. Owing to hot electron effects, the stimulated gain at 77 K is insensitive to the phonon resonance for pumping intensities larger than 400 kW/cm².