Abstract

The availability of sub 100 fs short and highly intense free-electron laser (FEL) pulses allows for new insights in laser-induced ultrafast demagnetization (LID) of ferromagnetic thin films on nanometer length scales. We designed a pair of in-vacuum Helmholtz coils, providing pulsed magnetic fields up to µ0Hz = ±45 mT, for time-resolved experiments at FEL sources in transmission geometry. We report on the implementation of the Helmholtz coils in an optical-pump–resonant-magnetic-scattering (tr-XRMS) experiment at the FEL FERMI (Elettra, Trieste) to study LID in different magnetic domain networks. We discuss the limitations for multi-shot measurements, that rely on the full reversibility of the demagnetization process in-between two pump–probe events, and emphasize the importance of reference–pump–probe schemes, especially in tr-XRMS experiments that employ external Hz fields.

Details

Title
In-vacuum Helmholtz coils for pulsed magnetic fields studying ultrafast demagnetization
Author
Riepp, M 1 ; Müller, L 1 ; Philippi-Kobs, A 2 ; Walther, M 1 ; Roseker, W 1 ; Rysov, R 1 ; Marotzke, S 3 ; Bagschik, K 1 ; Buck, J 2 ; Frömter, R 4 ; Wagner, J 4 ; Capotondi, F 5 ; Pedersoli, E 5 ; Naumenko, D 5 ; Kiskinova, M 5 ; Oepen, H P 4 ; Viefhaus, J 1 ; Grübel, G 1 

 Deutsches Elektronen-Synchrotron DESY , Notkestraße 85, 22607 Hamburg , Germany 
 Deutsches Elektronen-Synchrotron DESY , Notkestraße 85, 22607 Hamburg , Germany; Institut für Experimentelle und Angewandte Physik (IEAP), Christian-Albrechts-Universität zu Kiel , Leibnitzstraße 19, 24098 Kiel , Germany 
 Deutsches Elektronen-Synchrotron DESY , Notkestraße 85, 22607 Hamburg , Germany; Institut für Experimentelle und Angewandte Physik (IEAP), Christian-Albrechts-Universität zu Kiel , Leibnitzstraße 19, 24098 Kiel , Germany; Institut für Nanostruktur- und Festkörperphysik, Universität Hamburg , Luruper Chaussee 149, 22761 Hamburg , Germany 
 Institut für Nanostruktur- und Festkörperphysik, Universität Hamburg , Luruper Chaussee 149, 22761 Hamburg , Germany 
 Elettra Sincrotrone Trieste SCpA , Strada Statale 14 – km 163.5, 34149 Basovizza , Italy 
First page
012134
Publication year
2022
Publication date
Dec 2022
Publisher
IOP Publishing
ISSN
17426588
e-ISSN
17426596
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2757525662
Copyright
Published under licence by IOP Publishing Ltd. This work is published under http://creativecommons.org/licenses/by/3.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.