Abstract
A simple and robust refractive index (RI) sensor based on a Mach–Zehnder interferometer has been demonstrated. A section of optical microfiber drawn from silica fiber is employed as the sensing arm. Because of the evanescent field, a slight change of the ambient RI will lead to the variation of the microfiber propagation constant, which will further change the optical length. In order to compensate the variation of the optical length difference, a tunable optical delay line (ODL) is inserted into the other arm. By measuring the delay of the ODL, the ambient RI can be simply demodulated. A high RI sensitivity of about is achieved at microfiber diameter of 2.0 μm.
©2012 Optical Society of America
Full Article | PDF ArticleMore Like This
Haipeng Luo, Qizhen Sun, Zhilin Xu, Deming Liu, and Lin Zhang
Opt. Lett. 39(13) 4049-4052 (2014)
Haipeng Luo, Qizhen Sun, Xiaolei Li, Zhijun Yan, Yanpeng Li, Deming Liu, and Lin Zhang
Opt. Lett. 40(21) 5042-5045 (2015)
Jie Li, Li-Peng Sun, Shuai Gao, Zhan Quan, Yong-Liang Chang, Yang Ran, Long Jin, and Bai-Ou Guan
Opt. Lett. 36(18) 3593-3595 (2011)