Ultrafast dynamics in fieldhyphen;enhanced saturable absorbers

摘要

Absorption recovery dynamics of GaAs/AlGaAs fieldhyphen;enhanced waveguide saturable absorbers are studied by pumphyphen;probe differential transmission measurements. We compare the response of bulk and single quantum well absorbers at different reverse bias levels and pump powers, and find an ultrafast transient in the response, followed by a slower rise before the final recovery. The absorption fully recovers after a few picoseconds, which is an important result for modehyphen;locked lasers.