Femtosecond charge and spin dynamics in a Co50Pt50 alloy
The use of advanced x-ray sources plays a key role in the study of dynamic processes in magnetically ordered materials. The progress in x-ray free-electron lasers enables the direct and simultaneous observation of the femtosecond evolution of electron and spin systems through transient x-ray absorption spectroscopy and x-ray magnetic circular dichroism, respectively. Such experiments allow us to resolve the response seen in the population of the spin-split valence states upon optical excitation. Here, we utilize circularly polarized ultrashort soft x-ray pulses from the new helical afterburner undulator at the free-electron laser FLASH in Hamburg to study the femtosecond dynamics of a laser-excited CoPt alloy at the Co L<sub>3</sub>-edge absorption. Despite employing a weaker electronic excitation level, we find a comparable demagnetization for the Co 3<i>d</i>-states in CoPt compared to previous measurements on CoPd. This is attributed to the distinctly different spin-orbit coupling between 3<i>d</i> and 4<i>d</i> vs 3<i>d</i> and 5<i>d</i> elements in the corresponding alloys and multilayers.
Authors
- Clemens von Korff Schmising (ORCID: https://orcid.org/0000-0003-3159-3489)
- C. Schüßler-Langeheine (ORCID: https://orcid.org/0000-0002-4553-9726)
- E.A. Schneidmiller (ORCID: https://orcid.org/0000-0002-4832-1546)
- N. Pontius (ORCID: https://orcid.org/0000-0002-5658-1751)
- Mohamed F. Elhanoty (ORCID: https://orcid.org/0000-0002-0470-5767)
- Martin Pavelka
- Tim Amrhein (ORCID: https://orcid.org/0009-0003-7178-8173)
- Deeksha Gupta (ORCID: https://orcid.org/0009-0005-9472-1486)
- Siarhei Dziarzhytski (ORCID: https://orcid.org/0000-0003-3659-7702)
- Igor Vaskivskyi (ORCID: https://orcid.org/0000-0003-4090-1471)
- Simon Marotzke (ORCID: https://orcid.org/0000-0003-1514-5264)
- Ronny Knut (ORCID: https://orcid.org/0000-0001-6973-1205)
- Günter Brenner (ORCID: https://orcid.org/0000-0002-1755-876X)
- Somnath Jana (ORCID: https://orcid.org/0000-0001-8655-0545)
- Dieter Engel (ORCID: https://orcid.org/0000-0001-9255-9554)
- Oscar Grånäs (ORCID: https://orcid.org/0000-0002-1482-2182)
- Martin Beye (ORCID: https://orcid.org/0000-0002-3924-2993)
- H. A. Dürr (ORCID: https://orcid.org/0000-0001-9680-8730)
- Nele Thielemann-Kühn (ORCID: https://orcid.org/0000-0002-5259-3544)
- Ru‐Pan Wang (ORCID: https://orcid.org/0000-0003-4495-9881)
- Martin Weinelt (ORCID: https://orcid.org/0000-0002-5952-5130)
- Juliane Roensch-Schulenburg (ORCID: https://orcid.org/0000-0001-8901-2371)
Institutions
- Uppsala University (SE)
- Stockholm University (SE)
- Helmholtz-Zentrum Berlin für Materialien und Energie (DE)
- Deutsches Elektronen-Synchrotron DESY (DE)
- Jožef Stefan Institute (SI)
- Christian-Albrechts-Universität zu Kiel (DE)
- Max-Born-Institute for Nonlinear Optics and Short Pulse Spectroscopy (DE)
- Freie Universität Berlin (DE)
Publication Details
- Journal
- Structural Dynamics
- Published
- 2025-03-01
- DOI
- https://doi.org/10.1063/4.0000297
- Primary Topic
- Advanced X-ray Imaging Techniques
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Deutsche Forschungsgemeinschaft
- Bundesministerium für Bildung und Forschung
- Knut och Alice Wallenbergs Stiftelse
- Vetenskapsrådet
- Uppsala Universitet
- Helmholtz-Zentrum Berlin für Materialien und Energie
- Deutsches Elektronen-Synchrotron