title: Chromium/scandium multilayer mirrors for isolated attosecond pulses at 145  eV.
abstract: Recent advances in the development of attosecond soft x-ray sources toward photon wavelengths below 10 nm are also driving the development of suited broadband multilayer optics for steering and shaping attosecond pulses. We demonstrate that current attosecond experiments in the sub-200-eV range benefit from these improved optics. We present our achievements in utilizing ion-beam-deposited chromium/scandium (Cr/Sc) multilayer mirrors, optimized by tailored material dependent deposition and interface polishing, for the generation of single attosecond pulses from a high-harmonic cut-off spectrum at a central energy of 145 eV. Isolated attosecond pulses have been measured by soft x-ray-pump/NIR-probe electron streaking experiments and characterized using frequency-resolved optical gating for complete reconstruction of attosecond bursts (FROG/CRAB). The results demonstrate that Cr/Sc multilayer mirrors can be used as efficient attosecond optics for reflecting 600-attosecond pulses at a photon energy of 145 eV, which is a prerequisite for present and future attosecond experiments in this energy range.
authors.forename: Alexander
authors.initials: A
authors.lastname: Guggenmos
authors.forename: Michael
authors.initials: M
authors.lastname: Jobst
authors.forename: Marcus
authors.initials: M
authors.lastname: Ossiander
authors.forename: Stefan
authors.initials: S
authors.lastname: Radünz
authors.forename: Johann
authors.initials: J
authors.lastname: Riemensberger
authors.forename: Martin
authors.initials: M
authors.lastname: Schäffer
authors.forename: Ayman
authors.initials: A
authors.lastname: Akil
authors.forename: Clemens
authors.initials: C
authors.lastname: Jakubeit
authors.forename: Philip
authors.initials: P
authors.lastname: Böhm
authors.forename: Simon
authors.initials: S
authors.lastname: Noever
authors.forename: Bert
authors.initials: B
authors.lastname: Nickel
authors.forename: Reinhard
authors.initials: R
authors.lastname: Kienberger
authors.forename: Ulf
authors.initials: U
authors.lastname: Kleineberg