Erlangen 2018 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
K: Fachverband Kurzzeit- und angewandte Laserphysik
K 2: Optical Methods - Light and Radiation Sources
K 2.2: Vortrag
Montag, 5. März 2018, 16:45–17:00, MB HS
Ptychographic reconstruction and characterization of optical vortices — •Frederik Tuitje1,2, Michael Zürch1,2, and Christian Spielmann1,2 — 1Institute for Optics and Quantum Electronics, Abbe Center of Photonics, Friedrich Schiller University Jena, Germany — 2Helmholtz Institute Jena, Germany
Electromagnetic fields exhibiting helical phase profiles, so-called optical vortices (OV), are widely used in high-resolution imaging as structured light field, in spectroscopy to measure dipole-forbidden transitions and in particle manipulation. Recent research focusses on generating OV beams in the extreme ultraviolet regime via high harmonic generation [1]. In this spectral region, conventional beam characterization approaches for helical wavefronts are difficult to implement owing to the lack of efficient optical elements. Here, we present a method to fully characterize an optical vortex in amplitude and phase by employing ptychographic reconstructions following detection of a series of coherent diffraction patterns formed by a binary aperture. With this method, we can successfully reconstruct the helical phase of an OV yielding information about the topological charge, shape and size of the illuminating OV in unprecedented quality.
[1] Zürch, M.; Kern, C.; Hansinger, P.; Dreischuh, A.; Spielmann,C.: Strong-field physics with singular light beams. In: Nature Physics 8 (2012)