• Media type: E-Article
  • Title: Focusing hard x rays beyond the critical angle of total reflection by adiabatically focusing lenses
  • Contributor: Patommel, Jens; Klare, Susanne; Hoppe, Robert; Ritter, Stephan; Samberg, Dirk; Wittwer, Felix; Jahn, Andreas; Richter, Karola; Wenzel, Christian; Bartha, Johann W.; Scholz, Maria; Seiboth, Frank; Boesenberg, Ulrike; Falkenberg, Gerald; Schroer, Christian G.
  • imprint: AIP Publishing, 2017
  • Published in: Applied Physics Letters
  • Language: English
  • DOI: 10.1063/1.4977882
  • ISSN: 0003-6951; 1077-3118
  • Keywords: Physics and Astronomy (miscellaneous)
  • Origination:
  • Footnote:
  • Description: <jats:p>In response to the conjecture that the numerical aperture of x-ray optics is fundamentally limited by the critical angle of total reflection [Bergemann et al., Phys. Rev. Lett. 91, 204801 (2003)], the concept of adiabatically focusing refractive lenses was proposed to overcome this limit [Schroer and Lengeler, Phys. Rev. Lett. 94, 054802 (2005)]. We present an experimental realization of these optics made of silicon and demonstrate that they indeed focus 20 keV x rays to a 18.4 nm focus with a numerical aperture of 1.73(9) × 10−3 that clearly exceeds the critical angle of total reflection of 1.55 mrad.</jats:p>