Sub-nanograin metal based high efficiency multilayer reflective optics for high energies.
Arindam MajhiMaheswar NayakParesh Chandra PradhanShuvendu JenaAnil GomeManvendra Narayan SinghHimanshu SrivastavaVarimalla Raghvendra ReddyArvind Kumar SrivastavaAnil Kumar SinhaDinesh Venkatesh UdupaUllrich PietschPublished in: RSC advances (2021)
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.