Thermal ammonolysis of quasi-two-dimensional (quasi-2D) CoTa2O6 yields the O2-/N3- and anionic vacancy ordered Co2+Ta5+2O6-xN2x/3□x/3 (x ≤ 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.
@article{arxiv.2104.07804,
title = {Defect Engineered Room-Temperature Ferromagnetism in Quasi-Two-Dimensional Nitrided CoTa2O6},
author = {Yalin Ma and Shuang Zhao and Xiao Zhou and Yijie Zeng and Haili Song and Jing Wang and Guangqin Li and Corey E. Frank and Lu Ma and Mark Croft and Yonggang Wang and Martha Greenblatt and Dao-Xin Yao and Man-Rong Li},
journal= {arXiv preprint arXiv:2104.07804},
year = {2021}
}
Comments
9 pages, 7 figures; Supporting Information 27 pages, 17 figures