The features of surface plasmon resonance in gold cluster films

Abstract

The internal reflection of nanosized gold cluster films was studied using the technique of polarization modulation of electromagnetic radiation in the Kretschmann geometry. We measured the reflection coefficients Rs and Rp of s- and p-polarized radiation, respectively, as well as their polarization difference ∆R = Rs − Rp, as function of the light incidence angle in the 0.4÷1.6 µm wavelength range. A topological size effect was found; it consists in dependence of the value and sign of curvature of the polarization difference characteristics on the film surface properties. It is shown that the sign of curvature of ∆R characteristics depends on the radiation wavelength λ and indicates resonance interaction with a metal film of either p-polarized radiation only or that of both polarizations. The spectral characteristic of the topological size effect in the resonance interaction is obtained from the condition of isotropic reflection, ∆R = Rs − Rp = 0, and its dependence on the radiation wavelength.