1SECOND-ORDER NONLINEAR OPTICAL RESPONSE OF COLLOIDAL GOLD LABELED HUMAN SERUM IGG

AbstractHyper-Rayleigh scattering (HRS) technique was used to study the second-order nonlinear optical properties of colloidal gold labeled human serum IgG. The HRS experiments performed on protein-colloid conjugates display strong HRS signal at 532 nm when pumped with high intensity laser pulse with a wavelength of 1064 nm. The measured signal has a quadric intensity dependence on the pump laser energy indicating that the signal measured is indeed due to a second-order nonlinear optical process, namely, hyper-Rayleigh scattering. Thus, apparently for the first time, the hyper-Rayleigh scattering from nanocrystals bioconjugates has been observed