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arXiv · 2202.06424

Stable Ferromagnetism and High Curie Temperature in VGe$_2$N$_4$

Yingmei Li·Yong Liu
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Abstract

The discovery of monolayer MA$_2$Z$_4$ (M = transition metals; A = IVA elements; Z = VA elements, Science 369, 2020, 670-674) family has led another advance for facilitating and harnessing magnetism in low-dimensional materials. However, only Cr and V based MA$_2$N$_4$ compounds exhibit intrinsic magnetism yet with unsatisfied magnetic ordering temperature. Herein, we identify a stable ferromagnetic number of this family, i.e., VGe$_2$Z$_4$ monolayer, by means of first-principles calculations. It is found that the magnetic configuration sustains under both compression and tensile uniaxial in-plane strain, and the former can act as a positive modulator to enhance magnetic ordering temperature (Tc). Electronic structure calculations reveal a large band gap in the spin down channel while band-gapless in the spin up channel, an impressive near-half-metallic character, which is a favorable candidate for spintronic device.

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Yingmei Li, Yong Liu. 2022-02-13. Stable Ferromagnetism and High Curie Temperature in VGe$_2$N$_4$. https://doi.org/10.1088/1367-2630/ac8239

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