Design of novel titanium oxide/nickel oxide multilayer mirror for attosecond soft x rays

Abstract

A novel attosecond multilayer mirror was designed at “water-window” wavelengths with a combination of TiO and NiO, which were the same NaCl-type crystal structures of nearly equal lattice constants (TiO = 0.41766 nm, NiO = 0.41684 nm). The theoretical calculation of the TiO/NiO multilayer mirror indicated that the high reflectivity over 50% was attainable at 2.73 nm and at an incident angle of 18.9° from the normal incidence. Moreover, it also indicated that stacking of some multilayer blocks with different periods became effective in reflecting attosecond soft x rays.