Self‐pulsating lasers with quantum well saturable absorber

Excitability and coherence resonance in lasers with saturable absorber.

We show that a laser with a saturable absorber, described by the Yamada model, displays excitability just below threshold. A small perturbation, for example, a small input pulse, can trigger a single high output pulse, after which the system relaxes back to the off state. In order to study possible applications, such as pulse reshaping and clock recovery, approximate expressions are given for t...

Saturable absorption in intracavity loss modulated quantum well lasers

Voltage, temperature, and intensity dependence of saturable absorption in InGaAs/InP multiple quantum wells are investigated and related to the lasing characteristics of intracavity loss modulated InGaAs/InP quantum well lasers. Bistability in the static laser light output/absorber voltage characteristic arises from the shape of the measured absorption/ voltage/intensity surface of the quantum ...

Graphene-clad microfibre saturable absorber for ultrafast fibre lasers

Graphene, whose absorbance is approximately independent of wavelength, allows broadband light-matter interactions with ultrafast responses. The interband optical absorption of graphene can be saturated readily under strong excitation, thereby enabling scientists to exploit the photonic properties of graphene to realize ultrafast lasers. The evanescent field interaction scheme of the propagating...

Passive mode-locking in semiconductor lasers with saturable absorbers bandgap shifted through quantum well intermixing

Mode locking using a type II multiple-quantum-well structure as a fast saturable absorber.

We demonstrate the application of a type II Al(x)Ga((1-x))As/AlAs multiple quantum well as a fast saturable absorber in a hybridly mode-locked dye laser. Type II multiple quantum wells are promising for this application because of the fast recovery of the saturated absorption with picosecond or even subpicosecond time constants. We obtain almost transform-limited pulses as short as 0.9 psec for...