Self-Assembled Graphene Membrane as an Ultrafast Mode-Locker in an Erbium Fiber Laser

A self-assembled graphene membrane produced at the liquid/air interface of reduced graphene oxide aqueous suspension is demonstrated as an excellent mode-locker in an erbium-doped soliton fiber laser. Formation of the self-assembled membrane is attributed to hydrophobic nature of graphene and considerable capillary force. Experiments showed that such graphene saturable absorbers with insertion loss less than 6 dB worked well in the laser cavity setup, verifying that the self-assembly method is reliable and practical. Moreover, the method is quite facile, cost-effective, and potentially suitable for large-scale production of graphene mode-lockers.