A Compact and Stable Temperature Sensor Based on a Gourd-Shaped Microfiber

A compact and stable temperature sensor based on a gourd-shaped microfiber is fabricated and experimentally demonstrated. Claddings of the two microspheric structured fibers, which constitute the gourd shape, are spliced together but their cores are not. The transmission spectrum of the sensor features interference fringe due to the cavity formed inside the gourd-shaped microfiber. Increasing temperatures results in a significant red shift of fringe dip wavelength with a slope of \sim 17.15 pm/°C. Linear and parabolic fitting are both done to the measurements, enabling temperature measurements with high sensitivity and accuracy. The high stability and reliability of the sensor are corroborated keeping at different temperatures.