Investigations on sensing properties of tapered photonic crystal fiber refractive index sensor

Abstract

In present study a multi-mode fiber (MMF) stubbed tapered photonic crystal fiber (PCF) has been fabricated for refractive index and temperature sensing. The sensing probe has been formed by stubbing MMF and tapered PCF with varying tapering length, between two standard single-mode fibers (SMF). It has been observed from the experiment that the tapering of PCF and its tapering length affect the sensitivity of proposed sensor. Maximum sensitivity of 1891 µW/RIU and 900 µW/RIU has been achieved for single and dual point tapered PCF, respectively and a good linear response for high refractive indices has been obtained by measuring the optical output powers. The fabricated sensor has also been characterized for temperature sensing. The temperature sensitivity of 30 nW/°C and 19 nW/°C has also been measured from both single and dual point tapered PCF, respectively, for the temperature variation from 30 °C to 80 °C at the interval of 5 °C.