Frequency scan spectra of surface plasmons excitation in an arbitrary multilayer system

In this paper, we have derived approximate formulas from the Fresnel formul as and pole expansion for the reflectivity and resonant frequency in an arb itrary multilayer system. In accordance with the results of simulation, we conclude that the resonant wavelength increases when the incidence angle de creases and the resonant frequency increases when the metal thickness incre ases. Moreover the sensitivity of the resonant frequency versus the metal t hickness is very large when the metal thickness is modulated from 10 nm to 60 nm. One can make use of these properties to fabricate the instrument of the metal film measurement. Besides, the resonant frequency is a function o f the environment dielectric constant. One can apply the property to the ch emical sensor based on surface plasmons (SPs) measurement.