Trapezium-shaped groove photonic crystal fiber plasmon sensor for low refractive index detection

Abstract

A highly sensitive trapezium-shaped groove photonic crystal fiber (TSG-PCF) sensor based on surface plasmon resonance (SPR) is proposed and investigated numerically in low refractive index (RI) detection range of 1.181.30 by the finite element method (FEM). The trapezoidal groove is introduced, this sensor is simple in structure and manufactured easily. Indium tin oxide (ITO) is set as the sensing layer for the reaction between the core and the plasma. The influences of the structural parameters such as the holes parameters, the geometric parameters of the trapezium-shaped groove, the ITO layer thickness and other performance parameters on the design and sensing features of the proposed sensor are discussed comprehensively. The results show that for the proposed TSG-PCF, the maximum wavelength and amplitude sensitivities can arrive at 9100 nm/RIU and 99 RIU−1, the corresponding resolutions are 1.10 × 10−5 RIU and 1.01 × 10−4 RIU respectively in the analyte RI from 1.18 to 1.30. Moreover, the average sensitivity of 3429 nm/RIU can be realized for the appropriate parameters. The highly sensitive sensor makes the wide potential development for low RI detection in biological and chemical sensing.