Large Nonlinear Optical Absorption Response in Monolayer Graphene and Graphene Oxide

Abstract

Nonlinear absorption of monolayer graphene and graphene oxide suspensions were studied in the wavelength of 800 nm by Z-scan method with 50fs pulses. Large reverse saturable absorption is observed in graphene, while graphene oxide shows saturable absorption at the incident intensity of 46 GW/cm2. The values of nonlinear absorption coefficient also have been determined from the experimental data. The NLA coefficient β of the monolayer graphene suspension is 1.96×10-2cm/GW,while the NLA coeffiecient β of graphene oxide is-6.84×10-3cm/GW.

Determination of the Nonlinear Optical Properties of Single- and Few-Layered Graphene Dispersions under Femtosecond Laser Excitation: Electronic and Thermal Origin Contributions

“…In a similar study, Yang et al, 40 investigating the nonlinear absorption of bilayer graphene by means of the Z-scan technique, employing 1 kHz, 400 fs, 780 nm laser excitation, have observed RSA behavior and have determined a nonlinear absorption coefficient β of 32 × 10 −11 m W −1 , which is of the opposite sign and about 3 orders of magnitude larger than that determined here for the FLG samples consisting of 2−5 layers. In another work, Fan et al 41 studied the nonlinear absorption of SLG by means of the Z-scan technique using 1 kHz, 50 fs, 800 nm laser pulses. They have reported a strong RSA behavior and found a nonlinear absorption coefficient β of 0.196 × 10 −15 m W −1 , which is also of the positive sign and about 3 orders of magnitude smaller than that found here for the SLG samples.…”

Nonlinear optical and multi-photon absorption properties in graphene–ZnO nanocomposites

“…The NLO properties of the pure graphene and ZnO are also displayed in table 2. Some factors account for their different NLO properties: graphene performs different in suspension [43], in PMMA [35], and in dispersions [44]; GO performs different as films [45] and nanoparticles [46]; ZnO performs different when prepared in different environments (solvents, pressures), temperatures, with different processing cycles, and so on [42,[47][48][49][50][51][52]. The nonlinear absorption coefficients of graphene composites and ZnO composites are also shown in table 2 (PbS, Au, Ag, Cu, CdS, or Al) [47,[53][54][55]; they are greatly different from our results shown in table 1 both in the value of n b and absorption behavior.…”