高性能大尺寸X射线多层膜反射元件研制进展

Development of high performance and large size X-ray multilayer reflective optics

X射线多层膜是同步辐射与自由电子激光、天文观测、等离子体诊断等大科学装置和实验室分析仪器的重要光学元件,能高效率反射X射线并实现单色和偏振化等调控。本课题组在近二十年的工作中对X射线多层膜的设计、制备和表征方法开展了系统深入的研究,研制了一系列工作在软X射线和硬X射线不同波段的高性能多层膜,反射率达到国际先进水平;基于磁控溅射技术建立了大尺寸掠入射X射线多层膜的镀制平台,最大镀膜尺寸达1.2 m,均匀性优于0.5%(均方根值),制备的硬X射线多层膜反射镜成功应用在国内外大科学装置中;通过将多层膜与反射光栅相结合,创新发展了超高效率韧X射线多层膜光栅元件,相比传统单层膜光栅,该元件能将韧X射线衍射效率最高提升40倍。本文将简要介绍课题组在X射线多层膜元件领域的研究进展。

X-ray multilayers are key optical elements in synchrotron radiation and free electron laser facilities,astronomical observations,plasma diagnostics,and lab-based analytical instruments. They can realize highly efficient reflection,monochromatization,and polarization of X-rays. Our group has been conducting systematic studies on the design,fabrication,and characterization of X-ray multilayers during the past 20 years. We have developed a series of high-performance multilayers with world-class level reflectivity at different wavelengths and have built the deposition platform for large size X-ray multilayers based on the magnetron sputtering technique. The largest deposition mirror could achieve a length of 1. 2 m. The fabricated,hard X-ray multilayer mirrors have been successfully applied in synchrotron radiation facilities both in China and abroad. Through the combination of multilayer and reflective gratings,innovative,ultrahigh efficiency,tender,X-ray multilayer grating optics have been developed. Compared with conventional single-layer gratings,a maximum efficiency improvement of 40 times could be achieved. This study will introduce the results and progress that were achieved by our group in X-ray multilayer elements.