This paper proposes phase-shift-amplified optical fiber interferometry based on microwave photonics (MWP) for sensing applications with substantially-improved sensitivity. The principal idea of the system combines a destructive interference-based phase-shift amplification technique with optical carrier-based microwave interferometry (OCMI). The phase sensitivity of the OCMI system is significantly improved due to the phase amplifier, and more importantly, can be adjusted by simply varying the amplitude ratio of the two beams used in the interferometer. The amplification of the phase sensitivity is numerically investigated and experimentally demonstrated using a Mach-Zehnder interferometer for temperature and strain measurements. The measurement results accurately match theoretical predictions. Moreover, we demonstrate that light-scattering dots in the optical fiber core, created by tightly-focused femtosecond laser pulses, can be used to precisely tune the amplitude ratio of the two-beam interferometer. We postulate that amplification of several orders of magnitude in phase sensitivity can be achieved in the OCMI system by employing micromachining methods.

中文翻译：

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基于相移放大的超灵敏微波光子光纤干涉仪

本文提出了一种基于微波光子学（MWP）的相移放大光纤干涉测量技术，用于灵敏度显着提高的传感应用。该系统的主要思想是将基于破坏性干扰的相移放大技术与基于光载波的微波干涉测量法（OCMI）相结合。由于采用了相位放大器，OCMI系统的相位灵敏度得到了显着提高，更重要的是，可以通过简单地改变干涉仪中使用的两束光的振幅比来进行调整。使用Mach-Zehnder干涉仪进行温度和应变测量，对相位灵敏度的放大进行了数值研究和实验证明。测量结果与理论预测准确匹配。此外，我们证明了由紧密聚焦的飞秒激光脉冲在光纤芯中产生的光散射点可用于精确调整两光束干涉仪的振幅比。我们假设通过采用微加工方法，可以在OCMI系统中实现几倍数量级的相位灵敏度放大。