title: Focusing coherent soft-x-ray radiation to a micrometer spot size with an intensity of 10(14) W/cm2.
abstract: We investigate the focusability of intense coherent soft-x-ray radiation generated by high-order harmonic conversion. The 27th-harmonic wave at 29.6 nm is focused by an off-axis parabolic mirror with a SiC/Mg multilayer coating. Focal-spot images are observed from the visible fluorescence induced by the soft-x-ray photons on a Ce:YAG scintillator. We demonstrate focusing of the soft-x-ray beam to a 1-microm spot size with a peak intensity of 1 x 10(14) W/cm2, which is to our knowledge the highest ever reported in the soft-x-ray region.
authors.affiliation: Graduate School of Science and Engineering, Saitama University, 255 Okubo, Saitama-shi, Saitama 338-8570, Japan. m-hiro@riken.jp
authors.forename: Hiroki
authors.initials: H
authors.lastname: Mashiko
authors.forename: Akira
authors.initials: A
authors.lastname: Suda
authors.forename: Katsumi
authors.initials: K
authors.lastname: Midorikawa