title: High numerical aperture multilayer Laue lenses.
abstract: The ever-increasing brightness of synchrotron radiation sources demands improved X-ray optics to utilise their capability for imaging and probing biological cells, nanodevices, and functional matter on the nanometer scale with chemical sensitivity. Here we demonstrate focusing a hard X-ray beam to an 8 nm focus using a volume zone plate (also referred to as a wedged multilayer Laue lens). This lens was constructed using a new deposition technique that enabled the independent control of the angle and thickness of diffracting layers to microradian and nanometer precision, respectively. This ensured that the Bragg condition is satisfied at each point along the lens, leading to a high numerical aperture that is limited only by its extent. We developed a phase-shifting interferometric method based on ptychography to characterise the lens focus. The precision of the fabrication and characterisation demonstrated here provides the path to efficient X-ray optics for imaging at 1 nm resolution.
authors.affiliation: Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Morgan
authors.affiliation: Photon Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: Mauro
authors.initials: M
authors.lastname: Prasciolu
authors.affiliation: Faculty of Physics, University of Bialystok, K. Ciolkowskiego 1L, 15-245, Bialystok, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Andrejczuk
authors.affiliation: SLAC National Accelerator Laboratory, 2575 Sand Hill Rd., Menlo Park, CA 94025, USA.
authors.forename: Jacek
authors.initials: J
authors.lastname: Krzywinski
authors.affiliation: Photon Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: Alke
authors.initials: A
authors.lastname: Meents
authors.affiliation: Photon Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Pennicard
authors.affiliation: Photon Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: Heinz
authors.initials: H
authors.lastname: Graafsma
authors.affiliation: Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: Anton
authors.initials: A
authors.lastname: Barty
authors.affiliation: Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Bean
authors.affiliation: Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: Miriam
authors.initials: M
authors.lastname: Barthelmess
authors.affiliation: 1] Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany [2] Dept. of Physics, University of Hamburg, Luruper Chaussee 149, 22607 Hamburg, Germany.
authors.forename: Dominik
authors.initials: D
authors.lastname: Oberthuer
authors.affiliation: Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: Oleksandr
authors.initials: O
authors.lastname: Yefanov
authors.affiliation: European XFEL GmbH, Albert Einstein Ring 19, 22761 Hamburg, Germany.
authors.forename: Andrew
authors.initials: A
authors.lastname: Aquila
authors.affiliation: 1] Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany [2] Dept. of Physics, University of Hamburg, Luruper Chaussee 149, 22607 Hamburg, Germany [3] Centre for Ultrafast Imaging, Luruper Chaussee 149, 22607 Hamburg, Germany.
authors.forename: Henry N
authors.initials: HN
authors.lastname: Chapman
authors.affiliation: Photon Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: Saša
authors.initials: S
authors.lastname: Bajt