Optical limiting properties of CdS nanowires

Intensity-dependent nonlinear optical transmission studies of cadmium sulfide (CdS) nanowires (∼ 50–100 nm diameter) suspended in dimethylformamide have been carried out in the visible region using the Z-scan technique with 7 ns pulses from the second harmonic of an Nd:YAG laser. The optical limiting threshold of CdS nanowires suspension was determined to be 1.3 J cm− 2, with normalized transmittance of 0.47, which is relatively lower when compared with those of many popular metal nanowire suspensions reported in the literature. Based on an effective three-photon absorption model, nonlinear absorption and nonlinear scattering were identified as the dominant processes for the measured reduced transmittance.