Binary Number Sequence Multilayer Structure Based Refractometric Optical Sensing Element

Abstract

New mod. 4 up count binary number sequence multilayer structures are suggested as refractometric-sensing elements, for sensing very small refractive index changes of a medium. Theoretical results show that these mod. 4 up count binary number sequence multilayer structures exhibit isolated narrow transmission peaks in their forbidden wavelength regions and a slight change in refractive index of material layers induce large peak shifts in the transmission spectra. These new up count binary number sequence multilayer based refractometric sensing elements are not only remarkably smaller, but are also more sensitive than photonic crystal based sensing element recently suggested by researchers.