Two-dimensional half-metals MSi2N4 (M = Al, Ga, In, Tl) with intrinsic p-type ferromagnetism and ultrawide bandgaps

Yi-Min Ding; Yiqi Huo; Gaojing Fang; Luo Yan; Yu Wu; Liujiang Zhou

doi:10.1039/d3cp05940e

Two-dimensional half-metals MSi₂N₄ (M = Al, Ga, In, Tl) with intrinsic p-type ferromagnetism and ultrawide bandgaps

Phys Chem Chem Phys. 2024 May 1;26(17):13327-13334. doi: 10.1039/d3cp05940e.

Authors

Yi-Min Ding¹, Yiqi Huo², Gaojing Fang^{1

3}, Luo Yan^{1

2}, Yu Wu¹, Liujiang Zhou^{1

2}

Affiliations

¹ Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou 313001, China. ymding00@qq.com.
² School of Physics, University of Electronic Science and Technology of China, Chengdu 610054, China.
³ School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China.

PMID: 38639877
DOI: 10.1039/d3cp05940e

Abstract

Intrinsic half-metallic nanomaterials with 100% spin polarization are highly demanded for next-generation spintronic devices. Here, by using first-principles calculations, we have designed a class of new two-dimensional (2D) p-type half-metals, MSi₂N₄ (M = Al, Ga, In and Tl), which show high mechanical, thermal and dynamic stabilities. MSi₂N₄ not only have ultrawide electronic bandgaps for spin-up channels in the range of 4.05 to 6.82 eV but also have large half-metallic gaps in the range of 0.75 to 1.47 eV, which are large enough to prevent the spin-flip transition. The calculated magnetic moment is 1 μ_B per cell, resulting from polarized N1-p_x/p_y orbitals. Moreover, MSi₂N₄ possess robust long-range ferromagnetic orderings with Curie temperatures in the range of 35-140 K, originating from the interplay of N1-M-N1 superexchange interactions. Furthermore, spin dependent electronic transport calculations reveal 100% spin polarization. Our results highlight new promising 2D ferromagnetic half-metals toward future spintronic applications.