Lattice Dynamics and Phonon Dispersion of the van der Waals Layered Ferromagnet Fe<sub>3</sub>GaTe<sub>2</sub>
Xia Chen, Xi Zhang, Wenjie He, Yu Li, Jiating Lu, Dinghua Yang, Deren Li, Lei Li, Yong Peng, Gang Xiang
Abstract
Despite the tremendous progress in spintronic studies of the van der Waals (vdW) room-temperature ferromagnet Fe 3 GaTe 2, much less effort has been spent on studying its lattice dynamics and possible interaction with spintronic degrees of freedom. In this work, by combining Raman spectroscopy in a wide range of pressures (atmospheric pressure ∼19.5 GPa) and temperature (80–690 K) with first-principles calculations, we systematically studied the lattice dynamics and phonon dispersion of Fe 3 GaTe 2 . Our results show that the phonon energies of Fe 3 GaTe 2 located at 126.0 and 143.5 cm –1 originate from the anharmonic E 2 g 2 and harmonic A 1 g 1 vibration modes, respectively. Furthermore, the first room-temperature spin-phonon coupling in the vdW ferromagnet is observed with a strength of ∼0.81 cm –1 at 300 K, by identifying Raman anomalies in both phonon energy and full width at half-maximum of E 2 g 2 below the Curie temperature of Fe 3 GaTe 2 . Our findings are valuable for fundamental and applied studies of vdW materials under variable conditions.