Front. Optoelectron

Fiber up-taper assisted Mach-Zehnder interferometer for high sensitive temperature sensing

Lili MAO1,2,Qizhen SUN1,2,Ping LU1,2,*(),Zefeng LAO3,Deming LIU1,2

1. National Engineering Laboratory for Next Generation Internet Access System, Huazhong University of Science and Technology, Wuhan 430074, China 2. College of Optical and electronic information, Huazhong University of Science and Technology, Wuhan 430074, China 3. College of Electrical and electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074, China

Abstract

A new in-line Mach-Zehnder interferometer (MZI) sensor consisting of a stub of multi-mode fiber and an up-taper was proposed and demonstrated. Temperature measurement can be carried out by detecting wavelength shift. Dependency of sensitivity on interferometer length and dip wavelength was discussed. Experimental results showed a maximum temperature sensitivity of 113.6 pm/°C can be achieved, which is superior to most fiber temperature sensors based on in-line MZIs within the range from 20°C to 80°C, also a good mechanical strength can be obtained. The proposed sensor is a good candidate for temperature measurement, due to the advantages of simple structure, easy fabrication, cost-effective and high sensitivity.