Compact temperature-insensitive refractive-index sensor based on photonic crystal fiber

Abstract

A compact and simple fiber interferometer sensor suitable for external refractive index measurement is presented. By collapsing the air-holes of a PCF at a point along its length and forming a mirror at the end, we could get the reflection type interferometer. As a refractive index sensor, we show that the reflection spectrum of it moves to the longer wavelength direction with refractive index but is not affected by temperature.