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arXiv · 2104.07804

Defect Engineered Room-Temperature Ferromagnetism in Quasi-Two-Dimensional Nitrided CoTa2O6

Yalin Ma·Shuang Zhao·Xiao Zhou·Yijie Zeng·Haili Song·Jing Wang·Guangqin Li·Corey E. Frank·Lu Ma·Mark Croft·Yonggang Wang·Martha Greenblatt·Dao-Xin Yao·Man-Rong Li
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Abstract

Thermal ammonolysis of quasi-two-dimensional (quasi-2D) CoTa2O6 yields the O2-/N3- and anionic vacancy ordered Co2+Ta5+2O6-xN2x/3$\Box$x/3 (x $\leq$ 0.15) that exhibits a transition from antiferromagnetism to defect engineered above room-temperature ferromagnetism as evidenced by diffraction, spectroscopic and magnetic characterizations. First-principles calculations reveal the origin of ferromagnetism is a particular CoON configuration with N located at Wyckoff position 8j, which breaks mirror symmetry about ab plane. A pressure-induced electronic phase transition is also predicted at around 24.5 GPa, accompanied by insulator-to-metal transition and magnetic moment vanishing.

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Yalin Ma, Shuang Zhao, Xiao Zhou, Yijie Zeng, Haili Song, Jing Wang, Guangqin Li, Corey E. Frank, Lu Ma, Mark Croft, Yonggang Wang, Martha Greenblatt, Dao-Xin Yao, Man-Rong Li. 2021-04-15. Defect Engineered Room-Temperature Ferromagnetism in Quasi-Two-Dimensional Nitrided CoTa2O6. https://doi.org/10.1103/physrevb.104.014421

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