Realizing a Two-Dimensional Ferromagnet With High Curie Temperature and Low Damping: Cr_1.8Te₂

The rise of the 2D ferromagnets not only significantly advances fundamental physics and materials science but also provides excellent opportunities for various applications, particularly in spintronics. The 2D ferromagnets reported so far either show a Curie temperature (T_c) below room temperature (RT) or possess a high magnetic damping (α), which strongly limits their applications. Here, utilizing a state-of-the-art interconnected molecular beam epitaxy and magnetron sputtering system, we fabricate high-quality self-intercalated Cr_1.8Te₂ films and Cr_1.8Te₂/Pt heterostructures with clean interfaces. We find that the Cr_1.8Te₂ simultaneously achieves a high T_c (∼340 K) and a record-low α (∼0.02) among all 2D ferromagnets with T_c exceeding RT. These unique features enable the first observation of spin injection from a 2D ferromagnet via spin pumping in Cr_1.8Te₂/Pt bilayers under ambient conditions. Our findings establish self-intercalated Cr_1.8Te₂ as an efficient spin current source at RT, highlighting its great potential for practical spintronic applications.