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arXiv · 1610.00407

NiCl3 Monolayer: Dirac Spin-Gapless Semiconductor and Chern Insulator

Junjie He·Xiao Li·Pengbo Lyu·Petr Nachtigall
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Abstract

The great obstacle for practical applications of the quantum anomalous Hall (QAH) effect is the lack of suitable QAH materials (Chern insulators) with large non-trivial band gap, room-temperature magnetic order and high carrier mobility. The Nickle chloride (NiCl3) monolayer characteristics are investigated herein using first-principles calculations. It is reported that NiCl3 monolayers constitute a new class of Dirac materials with Dirac spin-gapless semiconducting and high-temperature ferromagnetism (~400K). Taking into account the spin-orbit coupling, the NiCl3 monolayer becomes an intrinsic insulator with a large non-trivial band gap of ~24 meV, corresponding to an operating temperature as high as ~280K at which the quantum anomalous Hall effect could be observed. The calculated large non-trivial gap, high Curie temperature and single-spin Dirac states reported herein for the NiCl3 monolayer lead us to propose that this material give a great promise for potential realization of a near-room temperature QAH effect and potential applications in spintronics. Last but not least the calculated Fermi velocities of Dirac fermion of about 4x105 m/s indicate very high mobility in NiCl3 monolayers.

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Junjie He, Xiao Li, Pengbo Lyu, Petr Nachtigall. 2016-10-03. NiCl3 Monolayer: Dirac Spin-Gapless Semiconductor and Chern Insulator. https://doi.org/10.1039/c6nr08522a

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