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DOE OSTI · 1862805

Covalent 2D Cr 2 Te 3 ferromagnet

Bian, Mengying·Kamenskii, Aleksandr N.·Han, Mengjiao·Li, Wenjie·Wei, Sichen·Tian, Xuezeng·Eason, David B.·Sun, Fan·He, Keke·Hui, Haolei·Yao, Fei·Sabirianov, Renat·Bird, Jonathan P.·Yang, Chunlei·Miao, Jianwei·Lin, Junhao·Crooker, Scott A.·Hou, Yanglong·Zeng, Hao
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Abstract

To broaden the scope of van der Waals 2D magnets, we report the synthesis and magnetism of covalent 2D magnetic Cr 2 Te 3 with a thickness down to one-unit-cell. The 2D Cr 2 Te 3 crystals exhibit robust ferromagnetism with a Curie temperature of 180 K, a large perpendicular anisotropy of 7 × 10 5 J m -3 , and a high coercivity of ~4.6 kG at 20 K. First principles calculations further show a transition from canted to collinear ferromagnetism, a transition from perpendicular to in-plane anisotropy, and emergent half-metallic behavior in atomically-thin Cr 2 Te 3 , suggesting its potential application for injecting carriers with high spin polarization into spintronic devices.

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2D magnets36 MATERIALS SCIENCECr2Te3High Magnetic Field ScienceMOKE microscopyhalf-metallicitymagnetic anisotropy

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Bian, Mengying, Kamenskii, Aleksandr N., Han, Mengjiao, Li, Wenjie, Wei, Sichen, Tian, Xuezeng, Eason, David B., Sun, Fan, He, Keke, Hui, Haolei, Yao, Fei, Sabirianov, Renat, Bird, Jonathan P., Yang, Chunlei, Miao, Jianwei, Lin, Junhao, Crooker, Scott A., Hou, Yanglong, Zeng, Hao. 2021-01-25. Covalent 2D Cr 2 Te 3 ferromagnet. https://doi.org/10.1080/21663831.2020.1865469

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