Signature for non-Stoner ferromagnetism in the van der Waals ferromagnet Fe3GeTe2

• DOI: 10.1103/physrevb.101.201104
• Publication Date: 2020-05-11T16:12:58Z
• Authors: X. Xu; Y. W. Li; S. R. Duan; S. L. Zhang; Y. J. Chen; L. Kang; A. J. Liang; C. Chen; W. Xia; Y. Xu; P. Malinowski; X. D. Xu; J.-H. Chu; G. Li; Y. F. Guo; Z. K. Liu; L. X. Yang; Y. L. Chen
• Keywords: Magnetism

The van der Waals ferromagnet $\mathrm{F}{\mathrm{e}}_{3}\mathrm{GeT}{\mathrm{e}}_{2}$ has attracted great research attention recently due to its extraordinary properties. Here, using high-resolution angle-resolved photoemission spectroscopy, we systematically investigate the temperature evolution of electronic structure bulk $\mathrm{F}{\mathrm{e}}_{3}\mathrm{GeT}{\mathrm{e}}_{2}$. We observe largely dispersive energy bands with exchange splitting that are in overall agreement our density-functional theory calculation. Interestingly, band dispersions barely change upon heating towards ferromagnetic transition near 225 K, except for reduction quasiparticle coherence, which strongly deviates from itinerant Stoner model. suggest local magnetic moments may play a crucial role ordering and $\mathrm{F}{\mathrm{e}}_{3}\mathrm{GeT}{\mathrm{e}}_{2}$, will shed light on generic understanding magnetism correlated materials.