Packaging of WGM resonator coupled with tapered fiber for various application scenarios

In this study, we proposed a packaging that couples light from a tapered fiber to a whispering gallery mode resonator. The packaging is suitable for a wide range of resonators, such as quartz rods and crystal microdisks. The device uses a self-designed brass base with a special flexible structure to realize the three-dimensional precision adjustment of the relative position of the resonator and the tapered fiber. This structural is different from the packaging proposed in previous studies. It can adjust the coupling state of the resonator by adjusting the relative position between the resonator and the tapered fiber. We demonstrated the coupling process using a crystal resonator as an example and demonstrated three typical coupling states of the WGM system. The packaging also has the advantages of high stability, small size, low cost, and high portability. In addition, we tested the long-term robustness of the packaging and verified the application of the packaging for magnetic field sensing and temperature tuning.