Structural characterization and low‐temperature properties of Ru/C multilayer monochromators with different periodic thicknesses. (19th October 2015)

• Record Type: Journal Article
• Authors: Jiang, Hui; He, Yan; He, Yumei; Li, Aiguo; Wang, Hua; Zheng, Yi; Dong, Zhaohui
• Is Part Of: Journal of synchrotron radiation. Volume 22:Part 6(2015)
• Page Start: 1379
• Page End: 1385
• Publication Date: 2015-10-19
• Subjects: multilayer -- cryogenic cooling -- interdiffusion -- interfacial roughness -- stress; Synchrotron radiation -- Periodicals; Free electron lasers -- Periodicals; 539.73505
• DOI: 10.1107/S1600577515017828
• Languages: English
• ISSNs: 0909-0495

Abstract

Abstract : Ru/C multilayer monochromators with different periodic thicknesses were investigated using X‐ray grazing‐incidence reflectivity, diffuse scattering, Bragg imaging, morphology testing, etc. before and after cryogenic cooling. Quantitative analyses enabled the determination of the key multilayer structural parameters for samples with different periodic thicknesses, especially the influence from the ruthenium crystallization. The results also reveal that the basic structures and reflection performance keep stable after cryogenic cooling. The low‐temperature treatment smoothed the surfaces and interfaces and changed the growth characteristic to a low‐frequency surface figure. This study helps with the understanding of the structure evolution of multilayer monochromators during cryogenic cooling and presents sufficient experimental proof for using cryogenically cooled multilayer monochromators in a high‐thermal‐load undulator beamline.