A novel and simple microfabrication method for in-line micro-cavity based fiber Mach–Zehnder interferometers (FMZIs) is proposed and demonstrated by nanosecond (ns) pulsed fibers lasers for the first time. Instead of using high-end femtosecond laser for the fabrication process, only conventional ns-pulsed fiber lasers of modest optical powers are required in our approach. Such fabricated fiber MZ interferometer has exhibited a high sensitivity of −20048 nm/RIU (refractive index unit) for the index sensing application. The achieved index sensitivity is in good agreement with the theoretical estimation.

中文翻译：

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纳秒脉冲制造的光纤马赫-曾德干涉仪及其在折射率传感中的应用

首次提出并通过纳秒 (ns) 脉冲光纤激光器演示了一种用于基于在线微腔的光纤 Mach-Zehnder 干涉仪 (FMZI) 的新颖且简单的微制造方法。我们的方法不需要使用高端飞秒激光器进行制造，而只需要具有适度光功率的传统 ns 脉冲光纤激光器。这种制造的光纤 MZ 干涉仪在折射率传感应用中表现出 -20048 nm/RIU（折射率单元）的高灵敏度。实现的指数敏感性与理论估计非常一致。