Carbon nanodots with strong nonlinear optical response

The carbon nanodots (CNDs) were synthesized by a simple method of femtosecond laser ablation of bagasse in ethanol. Strong optical limiting effects of as-prepared CNDs to 800 nm femtosecond laser pulses were observed with the threshold of 74 mJ/cm2. The strong two photon absorption of CNDs is responsible for the optical limiting response. The nonlinear coefficient was determined by the open-aperture Z-scan technique.