title: Damage threshold of platinum/carbon multilayers under hard X-ray free-electron laser irradiation.
abstract: We evaluated the irradiation damage induced by hard X-ray free-electron lasers to platinum/carbon multilayers intended for use in a focusing reflective mirror. In order to determine the damage threshold, we compared X-ray reflectivities before and after irradiation at the first-order Bragg angle using a focused X-ray free-electron laser with a beam size of approximately 1 μm and a pulse energy ranging from 0.01 to 10 μJ at a photon energy of 10 keV. We confirmed that the damage threshold of the platinum/carbon multilayer with a bilayer period of 3 nm was 0.051 μJ/μm(2), which is sufficiently higher than that in practical applications.
authors.forename: Jangwoo
authors.initials: J
authors.lastname: Kim
authors.forename: Ayaka
authors.initials: A
authors.lastname: Nagahira
authors.forename: Takahisa
authors.initials: T
authors.lastname: Koyama
authors.forename: Satoshi
authors.initials: S
authors.lastname: Matsuyama
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Sano
authors.forename: Makina
authors.initials: M
authors.lastname: Yabashi
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Ohashi
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ishikawa
authors.forename: Kazuto
authors.initials: K
authors.lastname: Yamauchi