Mina Eslamifar - Physics Department, Behbahan Khatam Alanbia University of Technology, Behbahan, Iran

This work focuses on the nonlinear properties of platinum nanoparticles (ptNPs) in the aqueous solution of sodium dodecyl sulfate (SDS) under irradiation of a continuous wave (CW) laser and a nanosecond pulse laser at the wavelength of ۵۳۲ nm. These properties are characterized by means of nonlinear transmittance, Z-scan technique, and scattered intensity assessments when submitted to laser operating at a wavelength of ۵۳۲ nm. The closed Z-scan measurements reveal thermal contribution for the nonlinear refractive index of the platinum nanoparticles in the CW regime and the saturable absorption is observed using the open aperture Z-scan method in the pulsed regime. It will be shown that the thermal thin lens model is in excellent agreement with the experimental results of the sample. A fit has allowed extracting the value of nonlinear refractive index to be -۱.۱×۱۰-۸ cm۲/W. The saturable absorption is analyzed using a phenomenological model based on nonlinear absorption and saturation intensity. The nonlinear absorption coefficient obtains ۳.۲ × ۱۰-۱۰ m-۱.

Platinum nanoparticles, Thermal nonlinear refraction, Saturable absorption, Z-scan technique