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arXiv · 2503.22483

Magnon-mediated terahertz spin transport in metallic Gd|Pt stacks

Oliver Gueckstock·Tim Amrhein·Beatrice Andres·Pilar Jiménez-Cavero·Cornelius Gahl·Tom S. Seifert·Reza Rouzegar·Ilie Radu·Irene Lucas·Marko Wietstruk·Luis Morellón·Martin Weinelt·Tobias Kampfrath·Nele Thielemann-Kühn
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Abstract

We study femtosecond spin transport in a Gd|Pt stack induced by a laser pulse. Remarkably, the dynamics of the spin current from Gd to Pt suggests that its dominant driving force is the ultrafast spin Seebeck effect. As the contribution of a transient spin voltage in the metal Gd is minor, Gd acts akin a magnetic insulator here. This view is supported by time- and spin-resolved photoemission, which indicates that a buildup of spin voltage is suppressed by exchange scattering, leading to similar amplitudes and relaxation rates of hot majority- and minority-spin electron populations.

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Oliver Gueckstock, Tim Amrhein, Beatrice Andres, Pilar Jiménez-Cavero, Cornelius Gahl, Tom S. Seifert, Reza Rouzegar, Ilie Radu, Irene Lucas, Marko Wietstruk, Luis Morellón, Martin Weinelt, Tobias Kampfrath, Nele Thielemann-Kühn. 2025-03-28. Magnon-mediated terahertz spin transport in metallic Gd|Pt stacks. https://arxiv.org/abs/2503.22483

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