A graphene-based saturable absorber device suitable for use in a ring-cavity fiber laser or a linear-cavity fiber laser is disclosed. The saturable absorber device includes an optical element and a graphene-based saturable absorber material supported by the optical element and comprising at least one of graphene, a graphene derivative and functionalized graphene. An examplary optical element is an optical fiber having an end facet that supports the saturable absorber material. Various forms of the graphene-based saturable absorber materials and methods of forming same are also disclosed.