Ptychographical imaging of the phase vortices in the x-ray beam formed by nanofocusing lenses

22nd International Congress on X-Ray Optics and Microanalysis

Dzhigaev, D.^1,2 ; Lorenz, U.^1,6 ; Kurta, R.P.^1 ; Seiboth, F.^3 ; Stankevic, T.^4 ; Mickevicius, S.^4 ; Singer, A.^1,7 ; Shabalin, A.^1 ; Yefanov, O.M.^5 ; Strikhanov, M.N.^2 ; Falkenberg, G.^1 ; Schroer, C.G.^3 ; Feidenhans'L, R.^4 ; Vartanyants, I.A.^1,2

Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, D-22607 Hamburg, Germany^1

National Research Nuclear University, MEPhI, 115409 Moscow, Russia^2

Institute for Structural Physics, Technische Universität Dresden, D-01062 Dresden, Germany^3

Niels Bohr Institute, University of Copenhagen, DK-2100 Copenhagen, Denmark^4

Center for Free-Electron Laser Science CFEL, Notkestraße 85, D-22607 Hamburg, Germany^5

Institut für Chemie, Universität Potsdam, Karl-Liebknecht-Straße 24-25, D-14476 Potsdam, Germany^6

University of California, San Diego, CA 92093, United States^7

关键词: Focal Plane;    Nanofocusing lens;    Object functions;    Optical axis;    Phase singularities;    Siemens stars;    Test object;    Vertical direction;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/499/1/012020/pdf
DOI  :  10.1088/1742-6596/499/1/012020

来源: IOP

【 摘 要 】

We present the ptychographical reconstruction of the x-ray beam formed by nanofocusing lenses (NFLs) containing a number of phase singularities (vortices) in the vicinity of the focal plane. As a test object Siemens star pattern was used with the finest features of 50 nm for ptychographical measurements. The extended ptychographical iterative engine (ePIE) algorithm was applied to retrieve both complex illumination and object functions from the set of diffraction patterns. The reconstruction revealed the focus size of 91.4±1.1 nm in horizontal and 70±0.3 nm in vertical direction at full width at half maximum (FWHM). The complex probe function was propagated along the optical axis of the beam revealing the evolution of the phase singularities.