Open AccessUltra-high sensitivity of dual dispersion turning point taper-based Mach-Zehnder interferometer
Author(s) -
Li-Peng Sun,
Tiansheng Huang,
Zihao Yuan,
Wenfu Lin,
Peng Xiao,
Mingjin Yang,
Jun Ma,
Yang Ran,
Jie Li,
BaiOu Guan
Publication year - 2019
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.27.023103
Subject(s) - optics , interferometry , refractive index , sensitivity (control systems) , mach–zehnder interferometer , materials science , dispersion (optics) , microfiber , physics , electronic engineering , composite material , engineering
We present here a detailed investigation into the sensitivity of the taper-based Mach-Zehnder interferometer as a function of external refractive index, with particular attention to the dispersion turning point (DTP) and possibilities for ultra-sensitive sensors. Our numerical simulation revealed that two DTPs exist with a decrease in the microfiber waist diameter; given this relationship, it is possible to obtain an ultra-sensitive operation. We then conducted experiments with fabricated devices with different waist diameters to achieve both positive and negative sensitivities at two DTPs. In particular, we achieved an ultrahigh refractive index sensitivity of approximately 95,832 nm/RIU at the second DTP when working with a diameter of 1.87 µm around the RI of air. These results show its potential for use in acoustic sensing and biochemical detection.