Solution-phase exfoliation of graphite for ultrafast photonics

We exfoliate graphite in both aqueous and non-aqueous environments through mild sonication followed by centrifugation. The dispersions are enriched with monolayers. We mix them with polymers, followed by slow evaporation to produce optical quality composites. Nonlinear optical measurements show ~5% saturable absorption. The composites are then integrated into fiber laser cavities to generate 630 fs pulses at 1.56 μm. This shows the viability of solution phase processing for graphene based photonic devices.