Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf
1 PublicationLaser-Rewriteable Ferromagnetism at Thin Film Surfaces
Ehrler, J.; He, M.; Shugaev, M. V.; Polushkin, N. I.; Wintz, S.; Liersch, V.; Cornelius, S.; Hübner, R.; Potzger, K.; Lindner, J.; Fassbender, J.; Ünal, A. A.; Valencia, S.; Kronast, F.; Zhigilei, L. V.; Bali, R.
Abstract
Manipulation of magnetism using laser light is considered a key to the advancement of data storage technologies. Until now, most approaches seek to optically switch the direction of magnetization rather than to reversibly manipulate the ferromagnetism itself. Here we use ~100 fs laser pulses to reversibly switch ferromagnetic ordering on and off by exploiting a chemical order-disorder phase transition in Fe60Al40, from the B2 to the A2 structure and vice versa. A single laser pulse above a threshold fluence causes non-ferromagnetic B2 Fe60Al40 to disorder and form the ferromagnetic A2 structure. Subsequent pulsing below the threshold reverses the surface to B2 Fe60Al40, erasing the laser induced ferromagnetism. Simulations reveal that the order-disorder transition is regulated by the extent of surface supercooling; above threshold the film melts-through and the consequent stability of the supercooled liquid phase suppresses vacancy diffusion, freezing the material into the disordered state. Pulsing below threshold forms a limited supercooled surface phase that solidifies at sufficiently high temperatures, enabling diffusion assisted reordering. This demonstrates that ultrafast lasers can achieve subtle atomic rearrangements in bimetallic alloys in a reversible and non-volatile fashion.
Keywords: magneto-optical devices; data storage; phase transitions; fs laser modifications; supercooling; order-disorder
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
-
Laser schaltet Magnet an und aus
ROBIS: 27530 cites this (Id 27198) publication -
Laser schaltet Magnet an und aus
DOI: 10.17815/jlsrf-3-159 is cited by this (Id 27198) publication
-
ACS Applied Materials and Interfaces 10(2018)17, 15232-15239
DOI: 10.1021/acsami.8b01190
Cited 31 times in Scopus
Downloads
- Final Draft PDF 2,3 MB Secondary publication
Permalink: https://www.hzdr.de/publications/Publ-27198
Years: 2023 2022 2021 2020 2019 2018 2017 2016 2015