Controlling linear and nonlinear optical properties associated with surface plasmon resonance effect of colloidal gold nanoparticles

In this work, we report on the successful use of myristic acid to modulate the SPR of AuNP dispersed in castor oil and the investigation of the third-order nonlinear optical response of the resulting colloidal systems.The colloids were prepared based on standard wet-chemical syntheses, employing aqueous solutions of HAuCl₄, as a gold source, KOH and castor oil. We observed that the colloids SPR frequency could be controlled adding myristic acid during the synthesis process as a tuning agent. Colloids with different filling factors (FF) were produced and characterized by TEM, UV-Vis spectroscopy, and atomic absorption spectrometry.