Abstract

The electric field in micro-optical fibers is affected by and is, therefore, an indicator of the ambient refractive index. Therefore, microfibers are widely used as refractive index sensors. In this paper, we studied the electric field of the microfiber, and the influence of the cladding radius was explored by using the semiweakly guide approximation. Next, the coupling ratio and the coupling radius were introduced as two indicators of the coupling efficient between the microfiber and the ordinary fiber. The results showed that the coupling ratio increases exponentially with the decrease of the cladding radius, and a sudden decrease of the coupling radius occurs when the cladding radius declines to a certain value. These results suggest that a stronger interference is available by a careful design of the cladding radius. The method introduced in this paper is also suitable to analyze the electric field under the influence of the surrounding refractive index for a given sensor.

© 2018 IEEE

Optical fiber axial micro-displacement sensor based on Mach-Zehnder interferometer

Changyu Shen, Youqing Wang, Jinlei Chu, Yanfang Lu, Yi Li, and Xinyong Dong
Opt. Express 22(26) 31984-31992 (2014)

Micro-fiber Mach–Zehnder interferometer based on ring-core fiber

Xuan Li, Nan-Kuang Chen, Lixia Xi, Hu Zhang, Xiaoguang Zhang, Wenbo Zhang, and Xianfeng Tang
Opt. Express 27(24) 34603-34610 (2019)

Mach-Zehnder interferometer based fiber-optic nitrate sensor

Abdullah Al Noman, Jitendra Narayan Dash, Xin Cheng, Hwa-Yam Tam, and Changyuan Yu
Opt. Express 30(21) 38966-38974 (2022)

Optical fiber sensor based on a radio frequency Mach–Zehnder interferometer

Tao Wei, Jie Huang, Xinwei Lan, Qun Han, and Hai Xiao
Opt. Lett. 37(4) 647-649 (2012)

Temperature-insensitive optical fiber two-dimensional micrometric displacement sensor based on an in-line Mach–Zehnder interferometer

Chuan Zhong, Changyu Shen, Yang You, Jinlei Chu, Xin Zou, Xinyong Dong, Yongxing Jin, and Jianfeng Wang
J. Opt. Soc. Am. B 29(5) 1136-1140 (2012)