基于楔形光纤的微管腔折射率传感器特性分析  

Characteristic analysis of a microtube cavity refractive index sensor based on wedge-shaped fiber

作　　者：陈炜垠 武向农[1] CHEN Weiyin;WU Xiangnong(School of Information and Mechanical and Electrical Engineering,Shanghai Normal University,Shanghai 201400,China)

机构地区：[1]上海师范大学信息与机电工程学院,上海201400

出　　处：《光通信技术》2025年第2期23-28,共6页Optical Communication Technology

摘　　要：针对现有的锥形光纤耦合微管腔回音壁模式(WGM)存在耦合区域锥腰部分的机械强度不高及鲁棒性较弱的问题,提出了一种基于楔形光纤(WSF)的微管腔折射率传感器。通过引入WSF端面来激发倏逝场并与微管腔耦合形成WGM,采用时域有限差分法(FDTD)建立理论模型,深入研究了楔角、管壁厚度及微管腔外径对折射率传感特性的影响。仿真结果表明:当楔角为20°,管壁厚度为1μm,微管腔外径为110μm时,传感器的折射率灵敏度为326.5 nm/RIU,品质因子为3.236×10^(3),分辨率为6.12×10^(-5)RIU;该传感器用于葡萄糖浓度检测时,灵敏度为0.085 nm/mM,分辨率为0.23 mM。To address the issues of low mechanical strength and weak robustness in the tapered waist region of existing tapered fiber-coupled microtube cavity whispering gallery mode(WGM)sensors,a microtube cavity refractive index sensor based on a wedge-shaped fiber(WSF)is proposed.By utilizing the evanescent field excited from the WSF end-face to couple with the microtube cavity and form WGM,a theoretical model is established using the finite-difference time-domain(FDTD)method.The effects of wedge angle,wall thickness,and microtube cavity outer diameter on refractive index sensing characteristics are thoroughly investigated.The simulation results show that when the wedge angle is 20°,the tube wall thickness is 1μm,and the microtube outer diameter is 110μm,the sensor achieves a refractive index sensitivity of 326.5 nm/RIU,a quality factor of 3.236×10^(3),and a resolution of 6.12×10^(-5)RIU.When used for glucose concentration detection,the sensor demonstrates a sensitivity of0.085 nm/mM and a resolution of 0.23 mM.

关 键 词：折射率传感 回音壁模式 楔形光纤 微管腔 

分 类 号：TN253[电子电信—物理电子学]