title: Near-room-temperature Chern insulator and Dirac spin-gapless semiconductor: nickel chloride monolayer.
abstract: A great obstacle for practical applications of the quantum anomalous Hall (QAH) effect is the lack of suitable QAH materials (Chern insulators) with a large non-trivial band gap, room-temperature magnetic order and high carrier mobility. Based on first-principles calculations it is shown here that a nickel chloride (NiCl3) monolayer has all these characteristics. Thus, the NiCl3monolayer represents a new class of Dirac materials with Dirac spin-gapless semiconducting properties and high-temperature ferromagnetism (∼400 K). Taking into account the spin-orbit coupling, the NiCl3monolayer becomes an intrinsic Chern insulator with a large non-trivial band gap of ∼24 meV, corresponding to an operating temperature as high as ∼280 K 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 NiCl3monolayer led us to propose that this material gives 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 fermions of about 4 × 105m s-1indicate very high mobility in NiCl3monolayers.
authors.affiliation: Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, 128 43 Prague 2, Czech Republic. lixiao150@gmail.com petr.nachtigall@natur.cuni.cz.
authors.forename: Junjie
authors.identifier: http://orcid.org/0000-0001-6447-7893
authors.initials: J
authors.lastname: He
authors.affiliation: Department of Physics, University of Texas at Austin, Austin, TX, USA.
authors.forename: Xiao
authors.identifier: http://orcid.org/0000-0002-9121-7883
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, 128 43 Prague 2, Czech Republic. lixiao150@gmail.com petr.nachtigall@natur.cuni.cz.
authors.forename: Pengbo
authors.identifier: http://orcid.org/0000-0002-1785-9861
authors.initials: P
authors.lastname: Lyu
authors.affiliation: Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, 128 43 Prague 2, Czech Republic. lixiao150@gmail.com petr.nachtigall@natur.cuni.cz.
authors.forename: Petr
authors.identifier: http://orcid.org/0000-0002-1628-7275
authors.initials: P
authors.lastname: Nachtigall