Humidity and particulate testing of a high-Q microcavity packaging comprising a UV-curable polymer and tapered fiber coupler

The high-Q maintenance of microcavities greatly challenges the microresonator-based practical application. In this paper, we analyze the theoretical model of the Q in the open air, indicating that the Q can be spoiled drastically in the open air. The Q spoiling factors are also demonstrated experimentally to show the Q spoiling which originated from the water and the particulate in the surroundings. Then we propose and realize the Q maintenance through constructing a sealed and packaged microcavity regime. In the packaged structure the Q decreases a little but a high Q larger than 106 can be achieved continuously. Moreover, the sealed structure has good performance to maintain the high Q for a long time with the standard deviation about 104, because the Q spoiling factors are isolated by the package layer. Additionally, the package also enhances the robustness. These merits can promote the practical application of the microcavities.