Temperature-dependent magnetic order of two-dimensional ferromagnetic Cr2Ge2Te6 single crystal

The vigorous development of two-dimensional materials has attracted much attention in fields including physics, chemistry, materials, and energy in recent years. As an important part among the two-dimensional (2D) material family, 2D ferromagnets provide unique physical properties and potential applications. However, the similarities and differences between two-dimensional ferromagnetic materials and traditional ferromagnetic materials in terms of magnetic properties have not been studied thoroughly. To this end, combining the ferromagnetic resonance (FMR) and superconducting quantum interference vibrating sample magnometer (SQUID VSM), we systematically study the changes in the internal magnetic order of the 2D van der Waals crystal Cr₂Ge₂Te₆ (CGT). As the temperature rising to Curie Temperature (T_C), the in-plane and out-of-plane resonance fields of CGT gradually merge into a same field, indicating the changes of anisotropic. The amplitude of ferromagnetic resonance shows a peak when the temperature is below T_C, which may be due to the competition between damping progress and magnetization degradation during the heating process. This work paves the way for a better understanding of the mechanism of two-dimensional ferromagnetism.