Photonic Crystal Fiber Based Optical Sensor for Biomedical Applications: A Review

Abstract

This paper describes the photonic crystal fiber based optical sensor for analyte sensing. For sensing the large dynamic range of analyte refractive index, we have studied the resonant properties of core guided modes and plasmon politron modes. The use of photonic crystal fiber enhances the phase matching between optical fiber core guided modes and plasmon modes. PCF bring new strength to the fabrication of surface plasmon resonance sensors since its distinctive capability of guiding the evanescent field penetration. In plasmonic sensors, at the time, the phase matching condition is achieved, surface plasmon polaritons mode may be excited and results in extreme resonance condition. Unknown bio-analyte index of refraction can be computed by measuring the resonance wavelength. The sharp deep resonance curve results in the enhancement of signal to noise ratio and biosensing performance. By improving the width and depth of resonance curve, which are the two critical parameters, the PCF sensor biosensing performance can be enhanced. Moreover the effect of the thickness of the metallic layers on the biosensing performance is also studied by further structure optimization.