Open AccessExperimental demonstration of enhanced self-amplified spontaneous emission by photocathode temporal shaping and self-compression in a magnetic wiggler
Author(s) -
Zhen Zhang,
J. Duris,
James MacArthur,
A. Zholents,
Zhirong Huang,
Agostino Marinelli
Publication year - 2020
Publication title -
new journal of physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.584
H-Index - 190
ISSN - 1367-2630
DOI - 10.1088/1367-2630/aba14c
Subject(s) - wiggler , physics , undulator , photocathode , optics , laser , synchrotron radiation , cathode ray , beam (structure) , free electron laser , ultrashort pulse , attosecond , electron , quantum mechanics
In this paper we demonstrate experimentally the generation of attosecond soft x-ray free-electron laser (XFEL) pulses based on a novel approach to enhanced self-amplified spontaneous emission. Instead of utilizing an external laser, we shape the electron beam at the cathode by laser pulse stacking. We enhance the high-current spike in the beam profile through a self-compression process which uses short-range coherent synchrotron radiation in a wiggler and a downstream magnetic chicane. The undulator taper is then matched with the energy chirp along the beam for attosecond XFEL generation. Start-to-end simulations are performed to demonstrate the proposed method. The measured spectra suggest that a ∼250 as pulse duration is achieved at ∼940 eV in the experiment.