High-Sensitivity D-Type Six-Hole PCF-SPR Sensor

Photonic crystal fiber (PCF) sensors based on surface plasmon resonance (SPR) have broad application prospects in biomedical sensing, food safety, chemical sensing, and other fields. However, many of the PCF-SPR sensors proposed so far have problems such as complicated structure, difficult fabrication, difficult fusion bonding with ordinary optical fibers, and low detection efficiency, which hinder the development of this technology. In order to reduce the difficulty of fiber fabrication, and improve the practicality of optical fiber, a D-type six-hole PCF-SPR sensor with a simple structure that can be fabricated easily is designed. In this structure, the cladding diameter is the same as that of the ordinary optical fiber, thus making it easier to fuse the two. By optimizing the structure of the sensor, the sensing characteristics are improved, as manifested by a maximum wavelength sensitivity and optimal resolution which are 36,000 nm/RIU and 2.78 x 10-6RIU, respectively, in conjunction with a detectable refractive index range of 1.3-1.395. Because of these advantages, including a simple structure and high sensitivity, the sensor has great potential and value in many fields, such as biomedical sensing, chemical sensing, and so on.