Dynamics of GaAs/AlGaAs microdisk lasers

Dynamic response of a GaAs/AlGaAs microdisk laser has been experimentally i nvestigated using femtosecond optical pumping. Below the lasing threshold, the delay time of the emission pulse from the microdisk hardly changes with the pump power. Above the lasing threshold, the delay time is shortened dr amatically, and it decreases with increasing the pump power. The theoretica l simulation based on the rate equations reproduces the experimental observ ation after the effect of carrier diffusion is taken into account. The simu lation result illustrates that the speed of a microdisk laser is limited ma inly by the carrier diffusion in the disk plane. (C) 2000 American Institut e of Physics. [S0003- 6951(00)04041-9].