Spin-correlated optical transitions in room-temperature ferromagnetic Fe3GaTe2

Fe3GaTe2 has been recently identified as a potential van der Waals (vdW) ferromagnetic material for spintronic devices, owing to long-range ferromagnetic order, strong perpendicular magnetic anisotropy, and high Curie temperature (TC) above room temperature. The band structure and electronic transitions are crucial for understanding magnetic properties of Fe3GaTe2, requiring a comprehensive investigation of the electronic behavior of Fe3GaTe2 under external magnetic fields. In this study, magnetic circular dichroism (MCD) spectroscopy was employed to examine the electronic transitions in Fe3GaTe2 at room temperature. Three distinct MCD peaks are clearly observed under the applied magnetic fields, which could correspond to three electronic transitions determined by first-principles density functional theory calculations of the band structure of Fe3GaTe2. Furthermore, the three transition bands would be correlated with the Fe d orbitals, as supported by the calculated orbital-resolved band structure of Fe3GaTe2. These findings offer insights into the electronic transitions and the underlying electronic structure in Fe3GaTe2, providing a basis for further fundamental research and potential applications in spintronic devices.