Sub-nanograin metal based high efficiency multilayer reflective optics for high energies

• Published in: RSC advances 2021-08, Vol.11 (45), p.2897-2815
• Main Authors: Majhi, Arindam, Nayak, Maheswar, Pradhan, Paresh Chandra, Jena, Suvendu, Gome, Anil, Singh, Manvendra Narayan, Srivastava, Himanshu, Reddy, Varimalla Raghvendra, Srivastava, Arvind Kumar, Sinha, Anil Kumar, Udupa, Dinesh Venkatesh, Pietsch, Ullrich
• Format: Article
• Language: English
• Subjects: Boron carbide; Chemistry; Gamma rays; Grain growth; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Multilayers; Optical properties
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/d1ra04412e

The present finding illuminates the physics of the formation of interfaces of metal based hetero-structures near layer continuous limit as an approach to develop high-efficiency W/B 4 C multilayer (ML) optics with ML periodicity varying d = 1.86-1.23 nm at a fixed number of layer pairs N = 400. The microstructure of metal layers is tailored near the onset of grain growth to control the surface density of grains resulting in small average sizes of grains to sub-nanometers. This generates concurrently desirable atomically sharp interfaces, high optical contrast, and desirable stress properties over a large number of periods, which have evidence through the developed ML optics. We demonstrate significantly high reflectivities of ML optics measured in the energy range 10-20 keV, except for d = 1.23 nm due to quasi-continuous layers. The reflectivities at soft gamma-rays are predicted. The present finding illuminates the physics of the formation of interfaces of metal based hetero-structures near layer continuous limit as an approach to develop high-efficiency W/B 4 C multilayer optics with varying periods at a fixed large layer pairs.