Dirac Nodes and Magnetic Order in M₂X₂ Transition‐Metal Chalcogenides (Phys. Status Solidi RRL 11/2018)

In recent years, Dirac materials have been widely investigated because of their electronic symmetry protections and possible technology applications. The challenge of multifunctional Dirac materials is the coupling of these properties to other degrees of freedom and order parameters. In article 1800181, Jason T. Haraldsen and co-workers examine the potential for the crossover of Dirac materials and magnetic states. Using density functional theory, the authors perform a computational analysis of the electronic and magnetic properties for the M2X2 transition-metal chalcogenides (TMCs), where M = Cr, Mn, and Fe and X = S and Se. It is discovered that these materials are quasi-two-dimensional honeycomb lattices consisting of a distorted tetrahedral crystal-field symmetry that exhibits metallic antiferromagnetic ground states. An analysis of the electronic structure shows the presence of nodal points that resemble Dirac nodes for all cases, which leads to the possibility of the realization of magnetic Dirac materials.