Picosecond dynamics of a gain-switched InGaAsP laser

Optical pulses are observed, with subpicosecond resolution, from an InGaAsP laser driven with 17 ps wide electrical pulses. The temporal profile of these gain-switched pulses is analyzed to obtain the transient and steady-state injected carrier densities in the active layer for dc biases above and below threshold. Gain-switched pulses as short as 13 ps FWHM are presented, and empirical results are compared to computer simulations. The implications of these results to pulse code modulation at very high bit rates are also discussed.