High-sensitivity birefringent and single-layer coating photonic crystal fiber biosensor based on surface plasmon resonance.

A birefringent single-layer coating photonic crystal fiber biosensor based on surface plasmon resonance is proposed to realize high sensitivity, which is easy to implement, in that only gold is deposited externally. The birefringent nature of the structure provides the sensor with high sensitivity. The results show that the biosensor can obtain the wavelength sensitivity of 15180 nm/refractive index unit (RIU) and high linearity with the analyte RI range of 1.40-1.43, corresponding to the resolution of 5.6818×10-6  RIU. Owing to the high sensitivity and simple structure, the proposed sensor can find important applications in biochemical and biological analyte detection.