P-dopant incorporation and influence on gain and damping behaviour in high-speed GaAs-based strained MQW lasers.

We investigate p-dopant incorporation and the influence of p-doping on the gain and damping behaviour in GaAs-based strained multiple quantum well lasers. By adding 5x10high18-2x10high19 cmhigh-3 beryllium doping to the active region of In0.35Ga0.65As/GaAs strained multiple quantum well lasers (4 QW's), we are able to demonstrate both very efficient high-speed modulation (20 GHz at a DC bias current of 50 mA) and the first semiconductor lasers to achieve a direct modulation bandwidth of 30 GHz under DC bias (heat-sink temperature is equal 25 degree C).