Sensitivity enhancement of a single-fiber Mach-Zehnder interferometer by sensitizing its interference length

摘要

This paper presents a simple and novel, to the best of our knowledge, methodology towards enhancement of the refractive index sensitivity of the single-fiber (SF) Mach-Zehnder interferometer (MZI) configuration, postfabrication, over a relatively large range from 1.3344 RIU to 1.4532 RIU. A SF-MZI configuration, fabricated indigenously by non-adiabatic tapering of the silica fiber at two places separated by a distance of similar to 3.6 cm, is sensitized with induced birefringence by keeping weights on its interference region. By sensitizing the configuration, its refractive index (RI) sensitivity is enhanced from 20.24 nm/RIU to 84.68 nm/RIU, post-fabrication, validating the theoretical predictions. The proposed process for enhancing the RI sensitivity of the SF-MZI, presented for the first time, shall be useful for many applications. (C) 2020 Optical Society of America