Highly Sensitive Low Loss Dual-Core Gold Coated Photonic Crystal Fiber Biosensor Based on Surface Plasmon Resonance

A low loss and highly sensitive gold nano-film externally coated dual core refractive index (RI) sensor using photonic crystal fiber (PCF) platform is proposed in this work. The perfectly matched layer (PML) is circled around to the external side of analyte to avoid the radiation of reflected power. The numerical analysis of the recommended sensor has been done in the analyte range from 1.33 to 1.42 in the
$x$
-polarization by means of the finite element method (FEM). The maximum amplitude sensitivity, maximum wavelength sensitivity, and sensor resolution are 1102.57
$RIU^{-1}$
, 19000 nm/RIU, and
$5.26\times 10^{-6}$
RIU, respectively, with maximum confinement loss as low as 0.173 dB/cm. So, due to the low loss and high sensitive characteristics, the proposed sensor can be used in detecting unknown chemical and analyte.