超低损耗激光薄膜的散射与机械损耗  

Scattering and mechanical loss of ultra-low loss laser coatings

作　　者：张锦龙[1] 王富美 方圣欢 焦宏飞[1] 程鑫彬[1] 王占山[1] ZHANG Jinlong;WANG Fumei;FANG Shenghuan;JIAO Hongfei;CHENG Xinbin;WANG Zhanshan(Institute of Precision Optical Engineering,MOE Key Laboratory of Advanced Micro-Structured Materials,Shanghai Frontiers Science Center of Digital Optics,Shanghai Professional Technical Service Platform for Full-Spectrum and High-Performance Optical Thin Film Devices and Applications,School of Physics Science and Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学物理科学与工程学院精密光学工程技术研究所,先进微结构材料教育部重点实验室,上海市数字光学前沿科学研究基地,上海市全光谱高性能光学薄膜器件与应用专业技术服务平台,上海200092

出　　处：《光学精密工程》2022年第21期2655-2677,共23页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.61975155,No.62061136008);上海市科学技术委员会科技计划项目(No.20JC1414600,No.21JC1406100);上海市级科技重大专项-人工智能基础理论与关键核心技术(No.2021SHZDZX0100);中央高校基本科研业务费专项资金。

摘　　要：超低损耗激光薄膜在引力波探测、光原子钟、光腔衰荡光谱等精密测量领域具有重要应用。激光谐振腔的腔长稳定性和总光学损耗决定了测量系统的灵敏度和信噪比。在薄膜材料、制备工艺和检测技术的发展下,薄膜光学损耗控制和热噪声研究方面取得了显著的进展。在光学损耗方面,薄膜吸收已能控制在亚10-6量级,薄膜散射成为光学损耗的主要因素。本文重点从缺陷诱导散射和界面散射两方面梳理了薄膜散射控制的研究思路和成果,通过光学因子设计和界面功率谱密度调控降低薄膜界面散射,建立了节瘤缺陷诱导散射的理论分析模型,阐明其物理机制,提出了缺陷诱导散射的控制技术。在热噪声研究方面,主要介绍薄膜机械损耗的物理机制,通过薄膜材料体系优化降低反射薄膜的机械损耗,持续改进薄膜机械损耗的表征方法。Ultralow-loss laser coatings have important applications in precision measurement fields such as gravitational wave detection,optical atomic clocks,and optical cavity ring-down spectroscopy. The cavity length stability and total optical loss of the laser resonator determine the sensitivity and signal-to-noise ratio of the measurement system. With the development of thin-film materials,fabrication processes and detection techniques,significant progress has been achieved in thin-film optical loss and thermal noise research.As regards optical loss,the absorption of the thin film can be controlled at the sub-ppm level,and the scattering of the thin film has become the main contributing factor of optical loss. This paper focuses on defectinduced scattering and interface scattering and presents the research ideas and achievements of thin-film scattering control. The interface scattering of thin films is reduced through optical factor design and interface power spectral density control. The theoretical analysis model of nodule defect-induced scattering is established,and the physical mechanism and the control technology of the defect-induced scattering are proposed. With regard to thermal noise research,this paper primarily introduces the physical mechanism of thin-film mechanical loss,presents the mechanical loss reduction of reflective coating through thin-film material optimization,and the corresponding improvement in the characterization method of mechanical loss.

关 键 词：激光薄膜 界面散射 节瘤缺陷 机械损耗 

分 类 号：TB43[一般工业技术] O484[理学—固体物理]