Femtosecond dynamics in semiconductor lasers: experiment and theory of 'dark pulse' formation

摘要

We track the continuous-wave and femtosecond dynamics of semiconductor lasers after femtosecond pulse injection. The recirculating pulse evolves into a quasistable ultrafast 'dark pulse', accounted for by a simple numerical model. We report high-dynamic-range femtosecond measurements on the evolution of ultrashort pulses in continuous-wave LDs. The experiments were performed on 770 nm AlGaAs and on 1.5 /spl mu/m InGaAsP edge-emitting quantum-well LDs. A single femtosecond pulse centred on the lasing wavelength is injected and the LD output is time-resolved by upconversion in a nonlinear crystal.