State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China.
Research Center for Convergence Networks and Ubiquitous Services, University of Science & Technology Beijing, Beijing 100083, China.
Sensors (Basel). 2020 Nov 16;20(22):6539. doi: 10.3390/s20226539.
In this paper, a hollow-core negative curvature fiber (HC-NCF) with high birefringence is proposed for low refractive index (RI) sensing based on surface plasmon resonance effect. In the design, the cladding region of the HC-NCF is composed of only one ring of eight silica tubes, and two of them are selectively filled with the gold wires. The influences of the gold wires-filled HC-NCF structure parameters on the propagation characteristic are investigated by the finite element method. Moreover, the sensing performances in the low RI range of 1.20-1.34 are evaluated by the traditional confinement loss method and novel birefringence analysis method, respectively. The simulation results show that for the confinement loss method, the obtained maximum sensitivity, resolution, and figure of merit of the gold wires-filled HC-NCF-based sensor are -5700 nm/RIU, 2.63 × 10 RIU, and 317 RIU, respectively. For the birefringence analysis method, the obtained maximum sensitivity, resolution, and birefringence of the gold wires-filled HC-NCF-based sensor are -6100 nm/RIU, 2.56 × 10 RIU, and 1.72 × 10, respectively. It is believed that the proposed gold wires-filled HC-NCF-based low RI sensor has important applications in the fields of biochemistry and medicine.
本文提出了一种基于表面等离子体共振效应的具有高双折射的空心负曲率光纤（HC-NCF），用于低折射率（RI）传感。在设计中，HC-NCF 的包层区域仅由一个八根二氧化硅管的环组成，其中两根选择性地填充了金丝。通过有限元法研究了金丝填充 HC-NCF 结构参数对传播特性的影响。此外，分别采用传统的约束损耗法和新颖的双折射分析方法评估了在低 RI 范围内（1.20-1.34）的传感性能。仿真结果表明，对于约束损耗法，金丝填充 HC-NCF 基传感器的最大灵敏度、分辨率和品质因数分别为-5700nm/RIU、2.63×10RIU 和 317RIU。对于双折射分析方法，金丝填充 HC-NCF 基传感器的最大灵敏度、分辨率和双折射分别为-6100nm/RIU、2.56×10RIU 和 1.72×10，分别。相信所提出的基于金丝填充 HC-NCF 的低 RI 传感器在生物化学和医学领域具有重要的应用。
