title: X-Ray Optics on a Chip: Guiding X Rays in Curved Channels.
abstract: We study the propagation of hard x rays in single curved x-ray waveguide channels and observe waveguide effects down to surprisingly small radii of curvature R≃10  mm and a large contour length s≃5  mm, deflecting beams up to 30°. At these high angles, about 2 orders of magnitude above the critical angle of total reflection θ(c), most radiation modes are lost by "leaking" into the cladding, while certain "survivor" modes persist. This may open up a new form of integrated x-ray optics "on a chip," requiring curvatures mostly well below the extreme values studied here, e.g., to split and to delay x-ray pulses.
authors.affiliation: Institut für Röntgenphysik, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, Göttingen, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Salditt
authors.affiliation: Institut für Röntgenphysik, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, Göttingen, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Hoffmann
authors.affiliation: Institut für Röntgenphysik, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, Göttingen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Vassholz
authors.affiliation: DESY Photon Science, Hamburg, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Haber
authors.affiliation: Institut für Röntgenphysik, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, Göttingen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Osterhoff
authors.affiliation: European Synchrotron Radiation Facility, Grenoble, France.
authors.forename: J
authors.initials: J
authors.lastname: Hilhorst