[1] Gong H P, Song H F, Zhang S L et al. Curvature sensor based on hollow-core photonic crystal fiber Sagnac interferometer[J]. IEEE Sensors Journal, 14, 777-780(2014).

[2] Gao P, Zhao Y, Li J. Temperature sensor with photonic crystal fiber filled with ethanol as probe[J]. Journal of Northeastern University (Natural Science), 36, 1369-1373(2015).

[3] Luo Y, Fan R H, Zhang Y P et al. Novel optical fiber refractive sensor fabricated with an alcohol-filled photonic crystal fiber based on a Mach-Zehnder interferometer[J]. Optical Fiber Technology, 48, 278-282(2019).

[4] Chen H L, Zheng Y, Li B C et al. Bubble microcavity strain and gravity sensor with temperature and bending insensitivity using an ultra-thin core optical fiber[J]. Optics & Laser Technology, 142, 107193(2021).

[5] Wang J, Pei L, Wang J S et al. A high sensitivity dual-parameter sensor based on glycerin filled fine-core polarization maintaining photonic crystal fiber[J]. Optical Fiber Technology, 55, 102139(2020).

[6] Peng M, Lu Z Q, Liu C N. Fiber optic sensor for simultaneous measurement of three parameters in FP cavity and MZI cascade[J]. Acta Optica Sinica, 43, 0106003(2023).

[7] Xu T T, Yang Y Q, Yang W L et al. Cascaded double-cavity temperature sensor based on hollow fibers encapsulated by PDMS membrane[J]. Acta Optica Sinica, 42, 0806004(2022).

[8] Yang Y H. Temperature sensor based on PNR in Sagnac interferometer[J]. Chinese Optics Letters, 2, 259-261(2004).

[9] Xu O, Lu S H, Feng S C et al. A novel fiber-laser-based fiber Bragg grating strain sensor with high-birefringence Sagnac fiber loop mirror[J]. Chinese Optics Letters, 6, 818-820(2008).

[10] Xu B, Zhao C L, Yang F et al. Sagnac interferometer hydrogen sensor based on panda fiber with Pt-loaded WO3/SiO2 coating[J]. Optics Letters, 41, 1594-1597(2016).

[11] Qi F, Xin Y, Dong X Y et al. Sagnac interferometer based temperature sensor with alcohol-filled side-hole fiber[J]. Laser & Optoelectronics Progress, 50, 010601(2013).

[12] Zhao J C, Zhao Y, Bai L et al. Sagnac interferometer temperature sensor based on microstructured optical fiber filled with glycerin[J]. Sensors and Actuators A, 314, 112245(2020).

[13] Shi M, Li S G, Chen H L. A high-sensitivity temperature sensor based on Sagnac interferometer employing photonic crystal fiber fully filled with ethanol[J]. Applied Physics B, 124, 94(2018).

[14] Lü L L, Liu Q, Xue P S. The sensing characteristics of microstructure-core photonic crystal fiber filled with liquid based on Sagnac interferometer[J]. Results in Physics, 18, 103198(2020).

[15] Zhao Y, Wu D, Lü R Q et al. Magnetic field measurement based on the Sagnac interferometer with a ferrofluid-filled high-birefringence photonic crystal fiber[J]. IEEE Transactions on Instrumentation and Measurement, 65, 1503-1507(2016).

[16] Wang H R, Zhang W, Chen C C et al. A new methane sensor based on compound film-coated photonic crystal fiber and Sagnac interferometer with higher sensitivity[J]. Results in Physics, 15, 102817(2019).

[17] Reyes-Vera E, Cordeiro C M B, Torres P. Highly sensitive temperature sensor using a Sagnac loop interferometer based on a side-hole photonic crystal fiber filled with metal[J]. Applied Optics, 56, 156-162(2017).

[18] Yang Y H, Wang H, Yang F L et al. Polarization-maintaining photonic crystal fiber hydrogen sensor based on Sagnac interferometer[J]. Acta Optica Sinica, 34, 0806004(2014).

[19] Han T T, Liu Y G, Wang Z et al. Control and design of fiber birefringence characteristics based on selective-filled hybrid photonic crystal fibers[J]. Optics Express, 22, 15002-15016(2014).

[20] Liu Y D, Chen H L, Chen Q et al. Experimental study on dual-parameter sensing based on cascaded Sagnac interferometers with two PANDA fibers[J]. Journal of Lightwave Technology, 40, 3090-3097(2022).

[21] Dong X Y, Tam H Y, Shum P. Temperature-insensitive strain sensor with polarization-maintaining photonic crystal fiber based Sagnac interferometer[J]. Applied Physics Letters, 90, 151113(2007).

[22] Naeem K, Kim B H, Kim B et al. Simultaneous multi-parameter measurement using Sagnac loop hybrid interferometer based on a highly birefringent photonic crystal fiber with two asymmetric cores[J]. Optics Express, 23, 3589-3601(2015).

[23] Rota-Rodrigo S, Perez-Herrera R A, Ibañez I et al. Multiwavelength fiber ring laser based on optical add-drop multiplexers and a photonic crystal fiber Sagnac interferometer[J]. Optics & Laser Technology, 48, 72-74(2013).

[24] Zuo J, Han T T, Yang J P et al. High sensitivity temperature sensor with an avoided-crossing based selective-filling high birefringent photonic crystal fiber Sagnac interferometer[J]. IEEE Access, 6, 45527-45533(2018).

[25] Kaczmarek C. Measurement of the temperature sensitivity of modal birefringence of polarization maintaining fibers using a Sagnac interferometer[J]. IEEE Sensors Journal, 16, 3627-3632(2016).

[26] Yang Y H, Yang F L, Wang H et al. Temperature-insensitive hydrogen sensor with polarization-maintaining photonic crystal fiber-based Sagnac interferometer[J]. Journal of Lightwave Technology, 33, 2566-2571(2015).

[27] Wu D, Zhao Y, Hu H F. Experimental research on FLM temperature sensor with an ethanol-filled photonic crystal fiber[J]. Sensors and Actuators A, 209, 62-67(2014).

[28] Akowuah E K, Gorman T, Ademgil H et al. Numerical analysis of a photonic crystal fiber for biosensing applications[J]. IEEE Journal of Quantum Electronics, 48, 1403-1410(2012).