Applied Physics Letters · 1994 · 85 citations · 11 references
EngineeringElectrical EngineeringMaterials ScienceOptoelectronicsPhotonicsSemiconductor MaterialsOptical Properties Of SemiconductorsQuantum WellsSaturable AbsorptionSemiconductor LasersSemiconductor PhysicsUltrafast OpticsMode-locked LasersOptical Absorption In Quantum WellsQuantum Well HeterostructuresReverse Bias CharacteristicsUltrafast Carrier DynamicsUltrafast Electron DynamicsUltrafast Laser DynamicsUltrafast Optical Response
Absorption recovery dynamics of GaAs/AlGaAs field-enhanced waveguide saturable absorbers are studied by pump-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 mode-locked lasers.
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