High sensitivity refractive index sensor based on the semicircular bent fiber

TL;DR

This paper introduces a highly sensitive refractive index sensor using a semicircular bent fiber, demonstrating a linear response and high sensitivity suitable for precise environmental measurements.

Contribution

The work presents a novel bent fiber design that achieves high sensitivity and linear response in refractive index sensing, with both theoretical and experimental validation.

Findings

Sensitivity of 1031 nm per refractive index unit

Linear decrease of resonant wavelength with increasing refractive index

Effective over a range of 1.3324 to 1.3435 RIU

Abstract

A refractive index sensor based on a semicircular bent fiber is presented. The interference occurs between the cladding mode excited in the bending region and the core mode. Both the theoretical and experimental results show that the resonant dip wavelength decreases linearly with the increase of the refractive index of the surrounding environment. A high sensitivity of 1031 nm per refractive index unit is obtained over the refractive index range of 1.3324 to 1.3435 by using a bent fiber with a bending radius of 500 {\mu}m.