Crystal growth and neutron diffraction studies of the new two-dimensional van der Waals ferromagnet Fe₃GaTe₂

Po-Chun Chang^1,2*, Sabreen Hammouda¹, Yung-Hsiang Tung¹, Yishui Zhou¹, ChaoHung Du², Yixi Su¹

¹Julich Centre for Neutron Science JCNS at Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Julich GmbH, Garching bei München, Germany
²Department of Physics, Tamkung University, New Taipei City, Taiwan

* Presenter:Po-Chun Chang, email:chang155212@gmail.com

Two-dimensional van der Waals (2D-vdW) ferromagnets are at the forefront of current condensed matter physics and materials science research due to their fascinating magnetic properties and massive potentials in such as spintronics and magnonics applications. Fe₃GaTe₂, having a hexagonal structure of space group P63/mmc, is a new 2D-vdW ferromagnet with an exceedingly strong easy c-axis magnetic anisotropy and a very high Curie temperature (T_c) at about 380 K. There are similarities between Fe₃GaTe₂ and the well-studied Fe_xGeTe₂ (x = 3~5), such as structure and magnetism. What appears striking is that Fe₃GaTe₂ has the best of both worlds: higher T_c and larger magnetic anisotropy than that of Fe₃GeTe₂, which makes Fe₃GaTe₂ particularly promising for potential applications. So far, there is only very little research about the mechanism of its magnetic order and magnetic anisotropy. Only one theoretical calculation on the exchange interactions was made, and the results also differed significantly from the exchange interaction of Fe₃GeTe₂. We have recently succeeded in the growth of high-quality Fe₃GaTe₂ single crystals, which have been comprehensively characterized by in-house measurements such as XRD and magnetometer, etc. We have also carried out a detailed single-crystal neutron diffraction study of the magnetic structure and phase transitions in Fe₃GaTe₂. Our new results, as well as some discussions about the nature of magnetism in this 2D-vdW magnetic material, will be given in this contribution.

Keywords: 2D-vdW, above-room-temperature ferromagnetism, Fe₃GaTe₂, Neutron scattering