Realizing a Two-Dimensional Ferromagnet With High Curie Temperature and Low Damping: Cr<sub>1.8</sub>Te<sub>2</sub>.

Yu, Longqian; Yang, Xi; Pang, Zhentao; Ren, Yifeng; Shen, Jiyu; Niu, Heng; Cheng, Jun; He, Kang et al. · Adv Mater · 2026

basic_science · Level V

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Abstract

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<sub>c</sub>) 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<sub>1.8</sub>Te<sub>2</sub> films and Cr<sub>1.8</sub>Te<sub>2</sub>/Pt heterostructures with clean interfaces. We find that the Cr<sub>1.8</sub>Te<sub>2</sub> simultaneously achieves a high T<sub>c</sub> (∼340 K) and a record-low α (∼0.02) among all 2D ferromagnets with T<sub>c</sub> exceeding RT. These unique features enable the first observation of spin injection from a 2D ferromagnet via spin pumping in Cr<sub>1.8</sub>Te<sub>2</sub>/Pt bilayers under ambient conditions. Our findings establish self-intercalated Cr<sub>1.8</sub>Te<sub>2</sub> as an efficient spin current source at RT, highlighting its great potential for practical spintronic applications.