title: Point focusing with flat and wedged crossed multilayer Laue lenses.
abstract: Point focusing measurements using pairs of directly bonded crossed multilayer Laue lenses (MLLs) are reported. Several flat and wedged MLLs have been fabricated out of a single deposition and assembled to realise point focusing devices. The wedged lenses have been manufactured by adding a stress layer onto flat lenses. Subsequent bending of the structure changes the relative orientation of the layer interfaces towards the stress-wedged geometry. The characterization at ESRF beamline ID13 at a photon energy of 10.5 keV demonstrated a nearly diffraction-limited focusing to a clean spot of 43 nm × 44 nm without significant side lobes with two wedged crossed MLLs using an illuminated aperture of approximately 17 µm × 17 µm to eliminate aberrations originating from layer placement errors in the full 52.7 µm × 52.7 µm aperture. These MLLs have an average individual diffraction efficiency of 44.5%. Scanning transmission X-ray microscopy measurements with convenient working distances were performed to demonstrate that the lenses are suitable for user experiments. Also discussed are the diffraction and focusing properties of crossed flat lenses made from the same deposition, which have been used as a reference. Here a focal spot size of 28 nm × 33 nm was achieved and significant side lobes were noticed at an illuminated aperture of approximately 23 µm × 23 µm.
authors.affiliation: Fraunhofer IWS Dresden, Winterbergstraße 28, 01277 Dresden, Germany.
authors.forename: Adam
authors.initials: A
authors.lastname: Kubec
authors.affiliation: Fraunhofer IKTS, Maria-Reiche-Straße 2, 01109 Dresden, Germany.
authors.forename: Kathleen
authors.initials: K
authors.lastname: Melzer
authors.affiliation: Fraunhofer IKTS, Maria-Reiche-Straße 2, 01109 Dresden, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Gluch
authors.affiliation: AXO DRESDEN GmbH, Gasanstaltstraße 8b, 01237 Dresden, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Niese
authors.affiliation: Fraunhofer IWS Dresden, Winterbergstraße 28, 01277 Dresden, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Braun
authors.affiliation: Institute of Structural Physics, Technische Universität Dresden, 01069 Dresden, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Patommel
authors.affiliation: ESRF, European Synchrotron Radiation Facility, Grenoble 30843, France.
authors.forename: Manfred
authors.initials: M
authors.lastname: Burghammer
authors.affiliation: Fraunhofer IWS Dresden, Winterbergstraße 28, 01277 Dresden, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Leson
keywords: X-ray nanofocusing; multilayer Laue lens; ptychography; scanning X-ray microscopy