AZO Coated Microchannel Incorporated PCF-Based SPR Sensor: A Numerical Analysis

An aluminum-doped zinc oxide (AZO) coated photonic crystal fiber (PCF) is proposed and numerically analyzed for surface plasmon resonance-based refractive index (RI) sensing. A microchannel is incorporated in this PCF, which is proposed to be fabricated using a pulsed laser. Such a structure is expected to have less roughness compared to that fabricated by mechanical polishing. Furthermore, properties such as no island formation and absence of intraband transition are added advantages of AZO. Numerical simulation shows that the maximum wavelength sensitivity and the corresponding resolution of this sensor are 5000 nm/RIU and 2 × 10-5RIU, respectively. Furthermore, the amplitude sensitivity is found to be as high as 167 RIU-1. The proposed structure can be easily fabricated and utilized for sensing applications as it does not require either coating of metals on the inner surface of holes of PCF nor filling of the voids of PCF and it requires a small amount of analyte for RI monitoring.