Comparison of the sensitivity of extraordinary transmittance peaks with the surrounding media for hole and slit arrays

In this paper we compare the sensitivity of the Extraordinary Transmittance (ET) peak position with the surrounding media for two types of metallic structures: arrays of holes and arrays of slits recorded in Au films. Both types of array were fabricated using Interference Lithography (IL) with a period of 700 nm and an Au thickness of 150 nm. The transmission spectra measurements were performed at normal incidence using a spectrophotometer. The results show that an array of slits presents a higher sensitivity for the surrounding media than the array of holes. Theoretical TE and TM simulations of the transmission spectra for the slit arrays agree very well with the experimental results, confirming the better sensitivity of the slit arrays.