Numerical Simulation of Optical Fiber Tamm Plasmon Polariton Sensor Based on D-Shaped Hollow-Core Photonic Crystal Fiber Coated With a Gold Film

An optical fiber Tamm plasmon polariton (TPP) sensor based on D-shaped hollow-core photonic crystal fiber (HCPCF) coated with a gold film is proposed. The mechanism of TPP excitation at the interface between 2-D photonic crystal (2DPC) and metal layer is explained by calculating the dispersion curves and electromagnetic field distributions of the fundamental core mode and the TPP mode. A narrow resonance peak with width of only a few nanometers appears in the photonic band gap of the HCPCF and shifts with the ambient refractive index (RI) change. A theoretical analysis about the influence of the structural parameters on the sensor performance is also carried out. The proposed sensor shows a maximum sensitivity of 3700 nm/RIU and figure of merit (FOM) of 1789 RIU
$^{{-{1}}}$
, which are much higher than that of optical fiber TPP sensors based on 1-D photonic crystal (1DPC). The feasibility of exciting TPP mode in HCPCF with inherent 2DPC cladding and its sensing application are demonstrated for the first time. Besides the reported optical fiber TPP sensor based on 1DPC, the results shown in this work will provide a new approach to the realization of the optical fiber TPP sensor.