Aperiodic multilayer structures in soft X-ray optics
E.N. Ragozinb,c aKansai Photon Science Institute, Japan Atomic Energy Agency, 8-1-7 Umemidai, Kyoto, Kizugawa-shi, 619-0215, Japan bMoscow Institute of Physics and Technology (National Research University), Institutskii per. 9, Dolgoprudny, Moscow Region, 141701, Russian Federation cLebedev Physical Institute, Russian Academy of Sciences, Leninsky prosp. 53, Moscow, 119991, Russian Federation
This paper reviews a series of studies that address the development and application of aperiodic multilayer structures (aperiodic multilayer mirrors) as soft X-ray (SXR) (λ ≈ 4—40 nm) optical elements. The paper discusses the potential of such structures for reflecting SXR radiation in a broad wavelength range, primarily at normal radiation incidence; and as polarization elements (broadband polarizer mirrors and phase shifters). The results of multiparametric optimization are presented, and experimental data for aperiodic Mo/Si (λ ⩾ 12.5 nm) multilayer mirrors are outlined. The feasibility of advancing to the λ ⩽ 12.5 nm domain due to the use of other materials is examined, and the capabilities of aperiodic structures as elements of attosecond SXR optics are discussed.