High-resolution and fast-response fiber-optic temperature sensor using silicon Fabry-Pérot cavity

Guigen Liu, Ming Han, Weilin Hou

91 Scopus citations

Abstract

We report a fiber-optic sensor based on a silicon Fabry-Pérot cavity, fabricated by attaching a silicon pillar on the tip of a single-mode fiber, for high-resolution and high-speed temperature measurement. The large thermo-optic coefficient and thermal expansion coefficient of the silicon material give rise to an experimental sensitivity of 84.6 pm/°C. The excellent transparency and large refractive index of silicon over the infrared wavelength range result in a visibility of 33 dB for the reflection spectrum. A novel average wavelength tracking method has been proposed and demonstrated for sensor demodulation with improved signal-to-noise ratio, which leads to a temperature resolution of 6 × 10-4 °C. Due to the high thermal diffusivity of silicon, a response time as short as 0.51 ms for a sensor with an 80-μm-diameter and 200-μm-long silicon pillar has been experimentally achieved, suggesting a maximum frequency of ∼ 2 kHz can be reached, to address the needs for highly dynamic environmental variations such as those found in the ocean.

Original languageEnglish (US)
Pages (from-to)7237-7247
Number of pages11
JournalOptics Express
Volume23
Issue number6
DOIs
StatePublished - Mar 23 2015

    Fingerprint

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

Cite this