Alterable interferential fineness for high temperature sensing calibration based on Bragg hollow core fiber

We propose, what we believe to be, a novel method for high temperature sensing calibration based on the mechanism of alterable interferential fineness in Bragg hollow core fiber (BHCF). To verify the proof-of-concept, the fabricated sensing structure is sandwiched by two sections with different length of BHCF. Two interferential fineness fringes dominate the transmission spectrum, where the high-fineness fringes formed by anti-resonant reflecting optical waveguide (ARROW) plays the role for high temperature measurement. Meanwhile, the low-fineness fringes induced by short Fabry-Perot (F-P) cavity are exploited as temperature calibration. The experimental results show that the ARROW mechanism-based temperature sensitivity can reach 26.03 pm/& DEG;C, and the intrinsic temperature sensitivity of BHCF is 1.02 pm/& DEG;C. Here, the relatively lower magnitude of the temperature sensitivity is considered as the standard value since it merely relies on the material properties of silicon. Additionally, a large dynamic temperature range from 100 & DEG;C to 800 & DEG;C presents linear response of the proposed sensing structure, which may shine the light on the sensing applications in the harsh environment.& COPY; 2023 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

We propose a novel method for high temperature sensing calibration based on alterable interferential fineness in Bragg hollow core fiber (BHCF). The sensing structure consists of BHCF sandwiched by two sections of different length. The high-fineness fringes formed by ARROW are used for high temperature measurement, while the low-fineness fringes induced by short F-P cavity are exploited for temperature calibration.