Spectral shift formation mechanisms in chemical sensor materials based on photonic crystals

Abstract

Photonic crystals are fabricated on two different substrates. The first structure consists of a PDMS-covered photonic crystal which is deposited on a PTFE film. The other one consists of a PDMS-covered photonic crystal which is deposited on a glass surface. Diffuse reflective spectra of both structures were analyzed. It was found that spectral shift induced by adding of the organic compound on a PDMS layer occurs only in the first structure. Estimations indicate the connection of diffuse spectral shifts with the effective refractive index and lattice parameter changing.

Keywords

• fotonic crystal, polystyrene microsphere, spectral shift, bragg reflection.