Saturable Absorber Based on Graphene-Covered-Microfiber

A polarization-dependent saturable absorber is developed by the use of graphene-polymer film covered microfiber. The evanescent field of the guided mode propagating along the microfiber can effectively interact with graphene. Polarization analysis shows that the single-layer graphene-based saturable absorber is more sensitive to polarization and has larger modulation depth than that of multi-layer graphene. Such a saturable absorber exhibits large saturable absorption power of >56.03 mW, and is easy to fabricate and compatible with optical fiber system. It has high potential in wide range of photonics applications.