2025/07/21 by Beier, Birte, Walendy, Erik, Arneth, Jan +3 · 1 citation
#FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Strongly Correlated Electrons (cond-mat.str-el)
paper · doi:10.48550/arxiv.2507.15366
We report a detailed high-field/high-frequency ferromagnetic resonance (HF-FMR) study of low-energy magnon excitations in the van der Waals ferromagnet Fe3GeTe2. At 2 K, the field dependence of the magnon branches is well described by a semiclassical domain-based model, from which we extract key microscopic parameters including the anisotropy gap Δ= 170± 4 GHz, the anisotropy field B\rm A = 5.85± 0.08 T, and the effective g-factor g\rm ab≃ g\rm c = 2.07(4). Furthermore the uniaxial anisotropy constant was determined to be K = (10.5± 0.23) × 10-6 erg/cm3. Anisotropic short-range magnetic order persists above T\rm C up to approximately 270 K, as evidenced by a finite anisotropy gap and anisotropic shifts in the FMR resonance fields. Both results clearly show the presence of anisotropic local magnetic fields well above T\rm C. Our findings underscore the crucial role of magneto-crystalline anisotropy in driving long-range magnetic order in Fe3GeTe2.