Twin Core Photonic Crystal Fiber Plasmonic Refractive Index Sensor

Abstract

This paper presents a highly sensitive plasmonic refractive index (RI) sensor on a dual-core photonic crystal fiber (PCF). The performance of the RI sensor is weighed in terms of amplitude sensitivity, wavelength sensitivity, wavelength resolution, and linearity of the resonance wavelength. Numerical result shows that the maximum amplitude sensitivity of 725.8918 RIU $^{-1}$ and 1085 RIU $^{-1}$ are achieved for $x$ - and $y$ -polarization, respectively, by using amplitude interrogation method. In addition, the wavelength interrogation method gives the maximum wavelength sensitivity of around 9000 nm/RIU for both $x$ - and $y$ -polarized modes. Moreover, the maximum wavelength resolution of $1.11\times 10^{-5}$ RIU and the value of the co-efficient of determination ( $\text{R}^{2}$ ) of 0.9784 are reported. The proposed high-performance plasmonic RI sensor can be a favorable candidate for the detection of biological and biochemical analytes.