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Ryan SA, Johnsen PC, Elhanoty MF, Grafov A, Li N, Delin A, Markou A, Lesne E, Felser C, Eriksson O, Kapteyn HC, Grånäs O, Murnane MM. Optically controlling the competition between spin flips and intersite spin transfer in a Heusler half-metal on sub-100-fs time scales. SCIENCE ADVANCES 2023; 9:eadi1428. [PMID: 37948525 PMCID: PMC10637748 DOI: 10.1126/sciadv.adi1428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 10/12/2023] [Indexed: 11/12/2023]
Abstract
The direct manipulation of spins via light may provide a path toward ultrafast energy-efficient devices. However, distinguishing the microscopic processes that can occur during ultrafast laser excitation in magnetic alloys is challenging. Here, we study the Heusler compound Co2MnGa, a material that exhibits very strong light-induced spin transfers across the entire M-edge. By combining the element specificity of extreme ultraviolet high-harmonic probes with time-dependent density functional theory, we disentangle the competition between three ultrafast light-induced processes that occur in Co2MnGa: same-site Co-Co spin transfer, intersite Co-Mn spin transfer, and ultrafast spin flips mediated by spin-orbit coupling. By measuring the dynamic magnetic asymmetry across the entire M-edges of the two magnetic sublattices involved, we uncover the relative dominance of these processes at different probe energy regions and times during the laser pulse. Our combined approach enables a comprehensive microscopic interpretation of laser-induced magnetization dynamics on time scales shorter than 100 femtoseconds.
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Affiliation(s)
- Sinéad A. Ryan
- JILA, University of Colorado Boulder, 440 UCB, Boulder, CO 80309, USA
| | - Peter C. Johnsen
- JILA, University of Colorado Boulder, 440 UCB, Boulder, CO 80309, USA
| | - Mohamed F. Elhanoty
- Division of Materials Theory, Department of Physics and Astronomy, Uppsala University, Box-516, SE 75120, Sweden
| | - Anya Grafov
- JILA, University of Colorado Boulder, 440 UCB, Boulder, CO 80309, USA
| | - Na Li
- JILA, University of Colorado Boulder, 440 UCB, Boulder, CO 80309, USA
| | - Anna Delin
- Department of Applied Physics, School of Engineering Sciences, KTH Royal Institute of Technology, AlbaNova University Center, SE-10691 Stockholm, Sweden
- Swedish e-Science Research Center (SeRC), KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden
- Wallenberg Initiative Materials Science for Sustainability, Uppsala University, 75121 Uppsala, Sweden
| | - Anastasios Markou
- Physics Department, University of Ioannina, 45110 Ioannina, Greece
- Max Planck Institute for Chemical Physics of Solids, 01187 Dresden, Germany
| | - Edouard Lesne
- Max Planck Institute for Chemical Physics of Solids, 01187 Dresden, Germany
| | - Claudia Felser
- Max Planck Institute for Chemical Physics of Solids, 01187 Dresden, Germany
| | - Olle Eriksson
- Division of Materials Theory, Department of Physics and Astronomy, Uppsala University, Box-516, SE 75120, Sweden
- Wallenberg Initiative Materials Science for Sustainability, Uppsala University, 75121 Uppsala, Sweden
| | - Henry C. Kapteyn
- JILA, University of Colorado Boulder, 440 UCB, Boulder, CO 80309, USA
- KMLabs Inc., Boulder, CO 80301, USA
| | - Oscar Grånäs
- Division of Materials Theory, Department of Physics and Astronomy, Uppsala University, Box-516, SE 75120, Sweden
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Kudryavtsev YV, Uvarov NV, Dubowik J. Optical properties of Fe-Mn-Ga alloys. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:235501. [PMID: 30919827 DOI: 10.1088/1361-648x/ab0cf3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The first-principles calculations of the electronic structures and the interband optical conductivity (OC) spectra have been performed for the stoichiometric Fe2MnGa alloy with L21 and L12 types of atomic ordering. The calculated optical properties of Fe2MnGa alloy for the L21 and L12 phases are complemented by the experimental OC spectra for bulk and thin film Fe-Mn-Ga alloy samples near the stoichiometry 2:1:1 with L21 and L12 (for bulks) as well as the body-centered-cubic and face-centered-cubic (for films) structures, respectively. A reasonable agreement between experimental and calculated interband OC spectra was obtained for both phases of the alloy. The experimental data show no significant difference in the OC spectra with respect to the degrees of atomic and magnetic orders of the samples.
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Affiliation(s)
- Y V Kudryavtsev
- Institute of Metal Physics, NAS of Ukraine, Vernadsky 36, 03142 Kiev, Ukraine
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