Passively Mode-Locked Fiber Laser Based on Reduced Graphene Oxide on Microfiber for Ultra-Wide-Band Doublet Pulse Generation

Graphene with zero-band gap can be easily saturated under strong excitation due to Pauli blocking. In this work, the graphene oxide membrane is reduced on the surface of microfiber by use of high temperature heating. Such reduced graphene oxide can interact with the strong evanescent field of the microfiber and enable saturable absorption in passively mode-locked fiber laser. The system can be effectively utilized to directly generate ultra-wide-band doublet pulses for high-capacity wireless communication applications.