[1] PANG Fufei, LIU Haoming, GUO Hairun, et al. Infiber MachZehnder interferometer based on double cladding fibers for refractive index sensor［J］. IEEE Sensors Journal, 2011, 11(10): 23952400.

[2] RONG Qiangzhou, QIAO Xueguang, WANG Ruohui, et al. Highsensitive fiberoptic refractometer based on a corediameter mismatch MachZehnder Interferometer［J］. IEEE Sensors Journal, 2012, 12(7): 25012505.

[3] YU Xiangzhi, LI Zhengyong, WANG Zhihao, et al. Effect of temperature and vibration on optical fiber MachZehnder interferometer and dynamic compensation［J］.Acta Photonica Sinica, 2012, 41(9): 10411046.

[4] GU Bobo, YIN Mingjie, ZHANG Aping, et al. Lowcost high performance fiberoptic pH sensor based on thincore fiber modal interferometer［J］. Optics Express, 2009, 17(25): 2229622302.

[5] TANG Changping ,DENG Ming, ZHU Tao, et al. Photonic crystal fiber based MachZehnder interferometer for refractive index measurement［J］.Journal of Optoelectronics Laser, 2011, 22(9): 13041308.

[6] TONG Zhengrong, HAN Wei, CAO Ye. Fiber sensor for simultaneous measurement of temperature and refraction index based on multimode fiber coreoffset［J］. Acta Optica Sinica, 2014, 34(1): 0106004.

[7] YANG Kai, XU Ben, LI Yi, et al. Highly sensitive temperature fiber sensor based on liquidsealed MachZehnder interferometer ［J］.Journal of Optoelectronics Laser, 2014, 25(7): 12591304.

[8] RODRIGUEZ A J, BALDOVINOPANTALEON O, DOMINGUEZ C R F, et al. Gasohol quality control for real time applications by means of a multimode interference fiber sensor［J］. Sensors, 2014, 14(9): 1781817828.

[9] GONG Huaping, SONG Haifeng, ZHANG Sulei, et al. An optical liquid level sensor based on polarizationmaintaining fiber modal interferometer［J］. Sensors and Actuators A, 2014, 205(1)： 204207.

[10] CHOI H Y, KIM M J, LEE B H. Allfiber MachZehnder type interferometers formed in photonic crystal fiber［J］. Optics Express, 2007, 15(9): 57115720.

[11] XUE Linlin, YANG Li. Sensitivity enhancement of RI sensor based on SMS fiber structure with high refractive index overlay［J］. Journal of Lightwave Technology, 2012, 30(10): 14631469.

[12] WANG Pengfei, BRAMBILA G, DING Ming, et al. Investigation of singlemode–multimode–singlemode and singlemodetapered multimodesinglemode fiber structures and their application for refractive index sensing［J］. Journal of Optical Society American B, 2011, 28(5): 11801186.

[13] LI Huidong, FU Haiwei, SHAO Min, et al. Infiber Mach Zehnder interferometer based on fiber core etched airbubble and core diameter mismatch for liquid refractive index sensing［J］. Acta Physia Sinica, 2013, 62(21): 214214.

[14] ZHANG Yunshan, QIAO Xueguang, SHAO Min, et al. Humidity sensor based on waistenlarged fiber tapers cascade structure［J］. Acta Photonica Sinica, 2015, 44(3): 03280040328004.

[15] WEI Tao, LAN Xinwei, XIAO Hai, Fiber inline core claddingmode MachZehnder interferometer fabricated by twopoint CO2 laser irradiations［J］. IEEE Photonics Technology Letter, 2009, 21(10): 669671

[16] WU Di, ZHU Tao, DENG Ming, et al. Refractive index sensing based on Mach–Zehnder interferometer formed by three cascaded singlemode fiber tapers［J］. Applied Optics, 2011, 50(10):1548 1553.

[17] BIAXOLI C R, SILVA S, FRANCO M A R, et al. Multimode interference tapered fiber refractive index sensors［J］. Applied Optics, 2012, 51(24): 59415945.

[18] LIU Qi, WANG Qin. Refractive index sensor based on tapered PCF inline interferometer［J］. Chinese Optics Letters, 2012, 10(9): 090601.

[19] YANG Rui, YU Yongsen, CHEN Chao, et al. Stapered fiber sensors for highly sensitive measurement of refractive index and axial strain［J］. Journal of Lightwave Technology, 2012, 30(19): 31263133.

[20] JEREMIE H, PING L， HUGO L, et al. Highly sensitive infiber interferometric refractometer with temperature and axial strain compensation［J］. Optics Express, 2013, 21(8): 999610009.

[21] TIAN Zhaobin, YAM S S H, BARNES J, et al. Refractive index sensing with MachZehnder interferometer based on concatenating two singlemode fiber tapers［J］. IEEE Photonics Technology Letter, 2008, 20(8):626629.

[22] LI Lecheng, XIA Li, XIE Zhenhai, et al. Allfiber MachZehnder interferometers for sensing applications［J］. Optics Express, 2011, 20(10): 1110911120.