An optical fiber Mach-Zehnder interferometer based on an inner air-cavity with an open micro-channel structure is presented. The device is fabricated by using femtosecond laser to inscribe a cavity structure in the optical fiber core, followed by discharging the cavity area with a fusion splicer to form an inner air-cavity in the fiber core, and finally create an open micro-channel with the help of hydrofluoric acid corrosion. The fiber in-line interferometric device is miniature, robust, and stable in operation and exhibits a high pressure sensitivity of ~3351 pm/MPa, with an extremely low temperature cross-sensitivity of 2.58 kPa/°C.

中文翻译：

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基于开放通道内气腔的光纤干涉仪用于气体压力传感


提出了一种基于开放式微通道结构内气腔的光纤马赫-曾德干涉仪。该装置的制作方法是利用飞秒激光在光纤纤芯中刻出空腔结构，然后用熔接机对空腔区域进行放电，在纤芯中形成内部气腔，最后在光纤纤芯中形成开放的微通道。借助氢氟酸腐蚀。该光纤在线干涉装置微型、坚固且运行稳定，具有约 3351 pm/MPa 的高压灵敏度和 2.58 kPa/°C 的极低温度交叉灵敏度。