  Whispering gallery mode (WGM) microcavities can confine photons within a
microscale volume for long periods of time, strongly enhancing light-matter
interactions, and making it a crucial platform in optical science and
applications. Current research on microcavity coupling system relays on precise
mechanical coupling with microscope monitoring, and its resonance properties
are extremely sensitive to external interference, which greatly limits the
practical application of microcavities. Therefore, a novel packaged
fiber-microcavity device with air/water tightness and stable temperature
characteristics is proposed in this paper. A variety of fixatives with
different Young's modulus gradients and low coefficients of thermal expansion
are used to design a package structure with overall vibration isolation and
buffering effect, in order to ensure the stability of the transmission spectrum
and improve the robustness of the microcavity module. Through the performance
characterization test of the device, it is proved that the packaged
microcavities can maintain a quality factor as high as 10^9, and has the
advantages of compact size, strong robustness, and versatility. This research
work is of great significance to promote the large-scale application of WGMs in
high-speed optical communication, nonlinear optics, narrow linewidth lasers,
and ultra-high sensitivity sensing.
