Gain compression and phase-amplitude coupling in GaInAs quantum well lasers with three, five and seven wells

The gain compression and phase-amplitude coupling factors are measured along with the differential gain in GaInAs/GaInAsP quantum well lasers with three, five and seven wells. Results are compared with those obtained for a conventional bulk laser of the same quaternary material. The ultimate modulation bandwidth deduced from the measurements is shown to increase with the number of wells. For the seven well laser, the ultimate modulation bandwidth is found to reasonably approach that obtained for the bulk laser while the phase-amplitude coupling factor is 2.6 times smaller.