Intrinsic modulation bandwidth of strained GaInP/AlGaInP quantum well lasers

We have investigated the intrinsic modulation response of ${\mathrm{Ga}}_x{\mathrm{In}}_{\text{1-x}}\mathrm{P/AlGaInP}$ quantum well lasers. The differential gain resulting from the measurement of the frequency response, is in good agreement with calculations based on a 6-band $\mathrm{kp}$ -theory and direct measurements of the optical gain. We find a maximum value of ${\text{3.8×10}}^{\text{−16}}$ ${\mathrm{cm}}^{\mathrm{2}}$ for a strongly compressively strained sample, which is less than in InGaAs lasers according to the larger effective masses. The maximum bandwidth we observed is 9.3 GHz at −3 dB. We show that the bandwidth is limited by catastrophic optical damage and not by intrinsic mechanisms.