In this work, spectral characteristics and temperature sensing characteristics of an in-line microfiber Mach-Zehnder interferometer (MZI) with an embedded microfiber knot resonator (MKR) is investigated. The microfiber MZI with an MKR (MZIKR) has a dual-effect composite spectrum with comb-like spectrum of the MKR loaded on the dominant interference spectrum. Vernier effect is generated by the MKR via superposition of resonant spectra with three resonant modes circulating in the MKR. This is the first time that Vernier effect is generated in a single MKR, which has advantages of easy fabrication and compact structure compared to the traditional resonant structures with Vernier effect such as two cascaded MKRs. Fast Fourier transform (FFT) and FFT filter are used to analyze and extract the different components of the transmission spectrum of the MZIKR. Temperature sensing characteristics of the different components of the polydimethylsiloxane-coated MZIKR are studied, showing that the interference dip of the MZI spectrum and the envelope dip of the MKR Vernier spectrum achieve a high temperature sensitivity of about -1.8 nm/ °C and about -3.5 nm/ °C, respectively. The proposed sensor has the advantages of easy fabrication, robust structure, and high sensitivity in temperature measurement. The MZIKR with dual-effect composite spectrum may have potential in two-parameter measurement and narrow-band filtering.

在这项工作中，研究了具有嵌入式微纤维结谐振器（MKR）的在线微纤维Mach-Zehnder干涉仪（MZI）的光谱特性和温度传感特性。具有MKR（MZIKR）的超细纤维MZI具有双重效应复合光谱，其MKR的梳状光谱负载在主要干扰光谱上。MKR通过共振光谱与MKR中循环的三个共振模式的叠加产生游标效应。这是首次在单个MKR中产生游标效应，与具有两个游标的MKR等具有游标效应的传统谐振结构相比，它具有易于制造和结构紧凑的优势。快速傅立叶变换（FFT）和FFT滤波器用于分析和提取MZIKR传输频谱的不同成分。研究了涂有聚二甲基硅氧烷的MZIKR的不同组分的温度传感特性，表明MZI光谱的干涉下陷和MKR Vernier光谱的包络下陷实现了约-1.8 nm /°C和约-的高温灵敏度。分别为3.5 nm /°C。所提出的传感器具有容易制造，坚固的结构以及在温度测量中的高灵敏度的优点。具有双效应复合频谱的MZIKR在两参数测量和窄带滤波中可能具有潜力。这表明MZI谱图的干扰下陷和MKR Vernier谱图的包络下陷分别达到约-1.8 nm /°C和-3.5 nm /°C的高温灵敏度。所提出的传感器具有易于制造，坚固的结构以及在温度测量中的高灵敏度的优点。具有双效应复合频谱的MZIKR在两参数测量和窄带滤波中可能具有潜力。这表明MZI谱图的干扰下陷和MKR Vernier谱图的包络下陷分别达到约-1.8 nm /°C和-3.5 nm /°C的高温灵敏度。所提出的传感器具有易于制造，坚固的结构以及在温度测量中的高灵敏度的优点。具有双效应复合频谱的MZIKR在两参数测量和窄带滤波中可能具有潜力。