Year: 2025
Type: article
Abstract: The laser excitation of magnetization dynamics without applying external fields is a topic of high interest for its potential applications (e.g., magnetic memories, oscillators, and THz emitters). We explore the use of an ultrashort infrared laser pulse for triggering transient changes in a magnetic vortex, probing the induced dynamics by time-resolved magnetic helicoidal dichroism (MHD) in resonant extreme ultraviolet scattering. MHD describes the optical response of a magnetic sample upon sign reversal of either the light orbital angular momentum or the magnetization and was demonstrated to be sensitive to the sample spin texture. Here, we show that, in addition to the well-known ultrafast demagnetization and remagnetization laser-induced processes, the analysis of the MHD signal, supported by micromagnetic simulations, provides direct evidence of important transient reorganizations of the spin texture. In particular, we find that an ultrafast laser pulse of sufficient intensity can induce a surface transient magnetic texture where the vortex curling direction is reversed with respect to the bulk. This result provides insight into the preparation of metastable complex spin states in magnetic films by optical methods without applying an external field, which is of relevance for novel applications in data storage and manipulation.
Source: Physical Review Letters
Authors: Mauro Fanciulli, Matteo Pancaldi, Anda-Elena Stanciu, Matthieu Guer, Emanuele Pedersoli, Dario De Angelis, Primož Rebernik Ribič, David Bresteau, Martin Luttmann, Pietro Carrara, Arun Ravindran, Benedikt Rösner, Christian David, Carlo Spezzani, Michele Manfredda, Ricardo Sousa, Laurent Vila, Ioan Lucian Prejbeanu, Liliana D. Buda-Prejbeanu, Bernard Dieny, Giovanni De Ninno, Flavio Capotondi, Thierry Ruchon, Maurizio Sacchi
Institutions: CY Cergy Paris Université, Laboratoire Interactions, Dynamiques et Lasers, University of West Bohemia in Pilsen, Ca' Foscari University of Venice, Elettra-Sincrotrone Trieste S.C.p.A., Institut de Recherche Interdisciplinaire de Grenoble, Spintronique et Technologie des Composants, Sorbonne Université, University of Nova Gorica, Paul Scherrer Institute, Synchrotron SOLEIL
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,750
Funders: European Cooperation in Science and Technology, Agence Nationale de la Recherche, Indo-French Centre for the Promotion of Advanced Research, Ministero dell’Istruzione, dell’Università e della Ricerca, Javna Agencija za Raziskovalno Dejavnost RS, Horizon 2020 Framework Programme, H2020 European Research Council
Awards: G1030326157, Structured light as a tool for triggering and probing new states of matter, Multiscale, multidimensional approach to chiral light-matter interactions for enhanced chiroptical responses, G2753325571, Helicoidal dichroism of magnetic structures, G7786534482, G8685623741, G8821370211
OpenAlex ID: W4409448283