Research On Manufacturing Technology Of All-fiber Mach-zehnder Interferometer Based On Micro-air Cavity

With the continuous advancement of science and technology,more and more fields have begun to use fiber optic interferometers,and the sensitivity and structure requirements of fiber optic interferometers in various fields are becoming higher and higher.Fiber optic Mach-Zehnder interferometer,as an important branch of fiber-optic interferometer,has many advantages and advantages,especially the all-fiber Mach-Zehnder interferometer based on micro air cavity has very important research value and practical significance.Therefore,in this paper,the manufacturing process of the all-fiber Mach-Zehnder interferometer based on the micro-air cavity is studied.The specific contents are as follows:The stress of the photonic crystal fiber in the V-groove is analyzed.The maximum linear load that the SM-7 solid core photonic crystal fiber can bear in the V-shaped fixture is0.10N/?m.The effects of fusion current,heating time and electrode offset on the air hole distortion of the photonic crystal fiber were investigated and analyzed during the low-loss fusion process of the photonic crystal fiber and single-mode fiber and the fusion process of forming the air cavity,and the photonic crystal fiber was explored.The best offset when welding with ordinary single-mode fiber is 49.25?m.Then,the effects of tensile force,welding current,welding time and electrode offset on the shape of the fiber micro air cavity were analyzed separately.Through FDTD simulation of the transmission spectrum corresponding to different shapes of air cavity,it is found that the transmission spectrum of the spindle-shaped micro air cavity has obvious peaks and troughs,so the spindle-shaped micro air cavity has better research significance.Combining the influence of welding parameters on the air holes of the photonic crystal fiber and the influence of the taper parameters on the micro air cavity,the welding parameters and the taper parameters corresponding to the spindle-shaped micro air cavity with different wall thicknesses are obtained.The characteristics of the spindle-shaped micro air cavity all-fiber Mach-Zehnder interferometer based on different wall thicknesses in refractive index sensing and strain sensing are studied.The sensitivity of the spindle-shapedmicro air cavity all-fiber Mach-Zehnder refractive index sensor can be achieved 1084 nm /RIU,the sensitivity of the all-fiber Mach-Zehnder strain sensor based on the spindle-shaped micro air cavity can reach 1 pm/??.