A Weakly Coupled Multi-core Fibre-based Michelson Interferometer Composed Of An In-fibre Coupler


A compact temperature measuring device using a weakly coupled multi-core fibre in the Michelson interferometer structure is proposed and experimentally demonstrated. The device is manufactured by an easy and simple splicing approach which consists of a multicore fibre segment and an in-fibre coupler. In-fibre coupler is made of a cascaded single-mode fibre and multi-core fibre balls. It enhances the interference phenomenon of light energy between the central core and the outer cores of a multi-core fibre. The sensor shows a high-quality fringe visibility of about 14–18 dB in the wavelength spectrum. Multi-core structure presents multi-path interferences and exhibits a maximum temperature sensitivity of 70.6 pm/°C in the range of 20–90°C with an insensitive response to the refractive index in the range of 1.334 to 1.354. The device has the advantages of compact size, easy manufacturing, and it solves cross-sensitivity between temperature and refractive index making it an authentic real-time temperature monitoring solution.


Electrical and Computer Engineering

Publication Status

Open Access


National Natural Science Foundation of China, Grant 51975442

Keywords and Phrases

In-fibre coupler; Michelson interferometer; Seven core fibre; Temperature sensor

International Standard Serial Number (ISSN)

1896-3757; 1230-3402

Document Type

Article - Journal

Document Version


File Type





© 2023 Polish Academy of Sciences, All rights reserved.

Publication Date

01 Jan 2021