Nonlinear Optical Response of Gold-Decorated Nanodiamond Hybrids

Abstract

Hybrids containing nanodiamonds with controllable content of gold nanoparticles (ND/Au) were prepared and characterized by XRD, TGA, and TEM/HRTEM techniques including STEM–EDS chemical mapping. For the first time, the nonlinear optical response of the prepared ND/Au dispersions in DMF was investigated by means of the Z-scan technique using 35 ps (532 and 1064 nm) and 40 fs (800 nm) laser excitations and is compared with that of neat nanodiamonds. The nanohybrids exhibited important nonlinear optical response, significantly larger than that of neat nanodiamonds under visible 35 ps laser excitation, while they were found to exhibit negligible nonlinear optical response when excited by 1064 nm, 35 ps, or 800 nm, 40 fs laser pulses. Gold loading was found to affect significantly their nonlinear optical properties, therefore providing an easy mean of modulation of their nonlinear optical response in view of different photonic and optoelectronic applications, such as optical limiters, optical switches, saturable absorbers, etc.