Surface plasmon resonance reflectance from nanoparticles in a liquid matrix: Retrieval of the optical properties using the maximum entropy model

Abstract

This paper summarizes recent developments in phase retrieval methods from surface plasmon resonance reflectance that are applied in the extraction of the complex effective refractive index of liquids containing nanoparticles. Both classical dispersion theory and the maximum entropy model (MEM) are considered. We show that the MEM is more suitable for a reflectance analysis, and it is applied to a variety of topologies with different volume fractions of nanoparticles in a solution. The MEM is always suitable for the extraction of the effective complex refractive index of the whole solution whereas the complex refractive index of constituent nanoparticles requires extraction using an effective medium theory. Therefore, a reliable model for the effective complex refractive index of the solution is needed. In this paper we give a summary of different effective medium theories that have been applied to describe the effective complex refractive index of nanoparticles in a liquid environment.