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Ksenzov D, Maznev AA, Unikandanunni V, Bencivenga F, Capotondi F, Caretta A, Foglia L, Malvestuto M, Masciovecchio C, Mincigrucci R, Nelson KA, Pancaldi M, Pedersoli E, Randolph L, Rahmann H, Urazhdin S, Bonetti S, Gutt C. Nanoscale Transient Magnetization Gratings Created and Probed by Femtosecond Extreme Ultraviolet Pulses. NANO LETTERS 2021; 21:2905-2911. [PMID: 33724854 DOI: 10.1021/acs.nanolett.0c05083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We utilize coherent femtosecond extreme ultraviolet (EUV) pulses from a free electron laser (FEL) to generate transient periodic magnetization patterns with periods as short as 44 nm. Combining spatially periodic excitation with resonant probing at the M-edge of cobalt allows us to create and probe transient gratings of electronic and magnetic excitations in a CoGd alloy. In a demagnetized sample, we observe an electronic excitation with a rise time close to the FEL pulse duration and ∼0.5 ps decay time indicative of electron-phonon relaxation. When the sample is magnetized to saturation in an external field, we observe a magnetization grating, which appears on a subpicosecond time scale as the sample is demagnetized at the maxima of the EUV intensity and then decays on the time scale of tens of picoseconds via thermal diffusion. The described approach opens multiple avenues for studying dynamics of ultrafast magnetic phenomena on nanometer length scales.
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Affiliation(s)
- Dmitriy Ksenzov
- Department Physik, Universität Siegen, Walter-Flex-Strasse 3, 57072, Siegen, Germany
| | - Alexei A Maznev
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | | | - Filippo Bencivenga
- Elettra Sincrotrone Trieste S.C.p.A., Strada Statale 14, km 163.5, 34149 Basovizza, Italy
| | - Flavio Capotondi
- Elettra Sincrotrone Trieste S.C.p.A., Strada Statale 14, km 163.5, 34149 Basovizza, Italy
| | - Antonio Caretta
- Elettra Sincrotrone Trieste S.C.p.A., Strada Statale 14, km 163.5, 34149 Basovizza, Italy
| | - Laura Foglia
- Elettra Sincrotrone Trieste S.C.p.A., Strada Statale 14, km 163.5, 34149 Basovizza, Italy
| | - Marco Malvestuto
- Elettra Sincrotrone Trieste S.C.p.A., Strada Statale 14, km 163.5, 34149 Basovizza, Italy
| | - Claudio Masciovecchio
- Elettra Sincrotrone Trieste S.C.p.A., Strada Statale 14, km 163.5, 34149 Basovizza, Italy
| | - Riccardo Mincigrucci
- Elettra Sincrotrone Trieste S.C.p.A., Strada Statale 14, km 163.5, 34149 Basovizza, Italy
| | - Keith A Nelson
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Matteo Pancaldi
- Department of Physics, Stockholm University, 106 91 Stockholm, Sweden
| | - Emanuele Pedersoli
- Elettra Sincrotrone Trieste S.C.p.A., Strada Statale 14, km 163.5, 34149 Basovizza, Italy
| | - Lisa Randolph
- Department Physik, Universität Siegen, Walter-Flex-Strasse 3, 57072, Siegen, Germany
| | - Hendrik Rahmann
- Department Physik, Universität Siegen, Walter-Flex-Strasse 3, 57072, Siegen, Germany
| | - Sergei Urazhdin
- Department of Physics, Emory University, Atlanta, Georgia 30322, United States
| | - Stefano Bonetti
- Department of Physics, Stockholm University, 106 91 Stockholm, Sweden
- Department of Molecular Sciences and Nanosystems, Ca' Foscari University of Venice, 30172 Venice, Italy
| | - Christian Gutt
- Department Physik, Universität Siegen, Walter-Flex-Strasse 3, 57072, Siegen, Germany
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