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arXiv · 2406.13273

Anisotropic magnetization dynamics in Fe5GeTe2 at room temperature

Alapan Bera·Nirmalya Jana·Amit Agarwal·Soumik Mukhopadhyay
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Abstract

The determination of Lande's g-factor and the damping constant is central to extracting crucial information about the spin-spin and spin-orbit interactions in magnetically ordered systems. In insulating compounds based on 3d elements, the spin-orbit interaction can be effectively probed by investigating the ground state of the corresponding free 3d ion within the crystalline environment. For metallic systems, the problem is non-trivial because of additional band structure effects. Here, we investigate the anisotropic magnetization dynamics in bulk single crystalline Fe5GeTe2, a van der Waals 2D itinerant ferromagnet at room temperature, using broadband ferromagnetic resonance spectroscopy. Strikingly, contrary to the results of ab-initio calculations, we do not observe any intrinsic anisotropy of magnetization damping close to room temperature, suggesting diminished role of spin-orbit interaction. However, there is a sizable anisotropy in the Lande's g factor near room temperature which is attributed to anisotropic critical spin fluctuations.

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Alapan Bera, Nirmalya Jana, Amit Agarwal, Soumik Mukhopadhyay. 2024-06-19. Anisotropic magnetization dynamics in Fe5GeTe2 at room temperature. https://doi.org/10.1103/physrevb.110.224401

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