LIGO（Laser Interferometer Gravitational-Wave Observatory）是一個專門設計用來探測引力波的天文設施，而LIGO Voyager是其下一代升級版本，其中一個主要目標是發展低溫技術以減少背景熱雜訊。干涉儀內部的高反射鏡用來傳輸光束，其薄膜的性能顯著影響LIGO的靈敏度和精度。本實驗室目前正致力於研究SiN及SiON薄膜，通過調整薄膜內部鍵結比例，發展具有低吸收率和低機械損耗的薄膜。此外，LPCVD方法被認為能產生性能更佳的薄膜，將成為未來薄膜研究的主要方向。在量測方面，我們正在開發一套新的機械損耗量測系統-GNS (Gentle Nodal Suspension)。與懸臂夾持系統相比，GNS的設計大幅減少了夾持面積，並簡化了樣品製作過程，從而可以減少額外的損耗並提升量測精確度。GNS發展初期遇到了致動器無法順利震動晶圓的困境，我將闡述我們通過哪些方法改進了系統並成功量測Ringdown訊號，以及系統目前的進展和未來的規劃。

LIGO (Laser Interferometer Gravitational-Wave Observatory) is an astronomical facility specifically designed to detect gravitational waves, and LIGO Voyager is its next-generation upgrade. One of its main goals is to develop cryogenic technologies to reduce background thermal noise. The high-reflectivity mirrors inside the interferometer are used to transmit light beams, and the performance of their coatings significantly affects the sensitivity and accuracy of LIGO.
Our laboratory is currently focused on researching SiN and SiON thin films. By adjusting the bonding ratio within the films, we aim to develop films with low absorption rates and low mechanical losses. Additionally, the LPCVD method is believed to produce films with better performance, making it the primary direction for future film research.
In terms of measurement, we are developing a new mechanical loss measurement system—GNS (Gentle Nodal Suspension). Compared to the cantilever clamping system, the GNS design significantly reduces the clamping area and simplifies the sample fabrication process, thereby reducing additional losses and improving measurement accuracy.
During the early development of GNS, we encountered difficulties with the actuator not being able to successfully vibrate the wafer. I will explain the methods we used to improve the system and successfully measure the ringdown signal, as well as the current progress and future goals of the system.

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