ABSTRACT
Objective: To measure the nonlinear refractive index and nonlinear absorption coefficient of Ag and Au particles
Design: A Quantitative Measurements
Setting: Royal College of Surgeons in Ireland [RCSI], Kingdom of Bahrain
Method: Ag and Au colloidal solutions were prepared by reduction processes. The nonlinear properties of the samples were investigated using CW laser at 488-514 nm using Z-scan technique
Result: Closed aperture z-scan displayed a pre-focal peak followed by a post-focal valley. These materials showed a large negative nonlinear refractive index of 5.85 X 10[-11] m[2]/W and 3.32 X 10[12]m[2]/W for silver and gold respectively and negative nonlinear absorption of 3.45 x 10[-4]m/W and 7.48 x 10[+5] m/W for silver and gold respectively
Conclusion: Z-scan showed that Ag and Au nanoparticles exhibit a nonlinear effect of thermal origin