超低损耗激光薄膜基础理论与关键技术研究

Laser-based precise measuring is one of the most important, advanced and cutting edge mesurement technologies in basic science, applications and national defense. The one, who could first get the most sensitive mesurement results, is more likely to be the first to discover new physical laws or to gain new technologies and to occupy academic commanding heights. Ultra-low loss laser coatings are the cornerstones for laser-based precise measuring and are the most critical elements that affect the measurement accuracy. The current research hotspot of ultra-low loss laser coatings is how to achieve a total loss that is less than 1 ppm. Ultra-low loss laser coatings have been widely used for military purpose, this research area is somewhat sensitive and there are only a few papers that dealt with Ultra-low loss laser coatings. Although China has made some achivements in ultra-low loss laser coatings up to now, the exploration on the loss mechanisms is still not deep and thorough. This hampers the furhter development of chinese own ultra-precise laser measuring techniques. So systematically investigating the basic theories and key technologies of ultra-low loss laser coatings is crucial for fundamental science and applications. This project will take the loss mechanisms as the research core and then guide the process optimization. We will deeply probe into the underlying physical root of scattering and absorption loss and explore the new mechanisms that mainly contribute to transmission loss. With the help of systematical and detailed study of loss mechanisms, the key technologies such as coating design, substrate polishing and cleaning, ion beam sputtering, post-processing and loss characterizing will be improved and perfected for the development of new, advanced and cutting edge ultra-precise laser measuring techniques.

超高精度激光测量是基础科学、应用技术和国防领域中重要的前沿测量技术，谁能最先得到高灵敏度的测量结果，谁就有可能发现新规律，掌握新技术，占领学术研究的制高点。超低损耗激光薄膜是这类测量系统的基石，也是影响精度最关键的元件，当前研究的热点和难点是如何将总损耗控制在1ppm以下。超低损耗激光薄膜广泛用于军事领域，内容敏感，国际上鲜有详细报导。到目前为止，我国虽然在这方面取得了一定的进展，但关于损耗机制研究的深度还不够，这为我国高精度、超灵敏激光测量系统的发展带来了障碍。因此研究超低损耗激光薄膜的基础理论和关键技术具有重要的科学意义和应用价值。本项目以损耗机制研究为龙头，带动制备技术改进，深入挖掘散射损耗和吸收损耗的物理根源，探寻关键的透射损耗新机制，进而有针对性地优化并完善薄膜设计、基板加工及清洗、离子束溅射镀膜、后处理和损耗检测等关键技术，为我国发展超高精度激光测试技术提供坚实的关键基础技术。

超高精度激光测量是基础科学、应用技术和国防领域中重要的前沿测量技术，超低损耗激光薄膜是实现这些测量系统的基石和核心元件。这些高精度激光测量系统的灵敏度、信噪比和性能强烈地依赖于薄膜的总损耗，没有性能优异的超低损耗激光薄膜，这些系统的优越性能，有时甚至是基本功能都是不可能实现的。超高精度激光测量技术的进步和发展迫切需要将薄膜的损耗降低至ppm甚至亚ppm水平。.天津津航技术物理研究所和同济大学合作开展了超低损耗激光薄膜基础理论与关键技术研究，针对超低损耗激光薄膜的极限光学性能问题，深入挖掘散射损耗和吸收损耗的物理根源，探寻关键的透射损耗新机制，创新性开展了亚微米量级缺陷表面散射与界面散射的控制技术、基于薄膜设计与能带调控的吸收损耗控制技术、超低损耗激光薄膜应力双折射控制技术、低压气体放电等离子环境薄膜损伤机制与控制技术等方面研究。在系统研究散射、吸收和透射损耗的基础上，建立了从薄膜设计、基板加工、基板清洗、离子束薄膜制备技术，后处理和损耗检测等一整套的闭环工艺流程，研制的超低损耗激光薄膜反射镜散射损耗0.3ppm，吸收损耗0.44ppm，透射损耗0.2ppm，总损耗小于1ppm。在项目研究过程中申请发明专利27项（授权11项），在核心以上学术期刊发表论文73篇。.本项目研究成果为我国发展超高精度激光测试技术提供坚实的关键基础技术。在实验中获得超低损耗激光薄膜损耗对激光陀螺精度的影响规律，验证超低损耗激光薄膜损耗性能的稳定性，为激光陀螺精度的提升提供技术支撑，将精度从0.005 °/h提升到0.0008 °/h，满足了我国新一代飞航导弹的发展需求，具有重要的科学意义和应用前景。