Mn₂C monolayer: a 2D antiferromagnetic metal with high Néel temperature and large spin–orbit coupling

Abstract

To realize antiferromagnetic spintronics in the nanoscale, it is highly desirable to identify new nanometer-scale antiferromagnetic metals with both high Néel temperature and large spin-orbit coupling. In this work, on the basis of first-principles calculation and particle swarm optimization (PSO) global structure search, we demonstrate that a two-dimensional Mn2C monolayer is an antiferromagnetic metal with a Mn magnetic moment of ∼3μB. Mn2C monolayer has an anti-site structure of MoS2 sheet with carbon atoms hexagonally coordinated by neighboring Mn atoms. Remarkably, the in-plane carrier mobility of 2D Mn2C is highly anisotropic, amounting to about 47 000 cm(2) V(-1) s(-1) in the a' direction, which is much higher than that of MoS2 monolayer. The Néel temperature of Mn2C monolayer is high up to 720 K. Due to strong spin-orbit coupling in plane, the magnetic anisotropy energy of Mn2C monolayer is larger than those of pure metals, such as Fe, Co, and Ni. These advantages render 2D Mn2C sheet with great potential applications in nanometer-scale antiferromagnetic spintronics.

MBene (MnB): a new type of 2D metallic ferromagnet with high Curie temperature

“…For the MnB sheet, the easy magnetization axis is the z direction (out-of-plane), along which the magnetization energy is lower than those along the x-and y-directions by 25 and 175 meV per Mn atom, respectively. These MAE values are comparable to those of reported 2D material Mn 2 C (25 meV) 32 and bulk Co (65 meV per Co atom), and are one order of magnitude higher than those of bulk Fe (1.4 meV per atom) and Ni (2.7 meV per atom). 45 The sizeable MAEs make the MnB sheet potentially useful for magnetoelectronic applications.…”

Mn2C Monolayer: Hydrogenation/Oxygenation-Induced Strong Ferromagnetism and Potential Applications

“…Our calculations find the 2H structure has the lowest energy among these structures, which is consistent with former computations. 31 As shown in Fig. 1(a), the 2H-type Mn 2 C monolayer manifests a honeycomb lattice with the D 3h symmetry, In the side view, it exhibits a triple-layer configuration with atomic layers stacked in the sequence of Mn−C− Mn, as shown in Fig.…”

“…Our results are consistent with previous computations. 31 Under the ground state, the total and projected density of states (DOS) for Mn 2 C monolayer is shown in Fig. 2 (e). It obviously manifests a metallic electronic structure with sizable DOS at the Fermi level.…”

Bistability and relaxor ferrimagnetism in off-stoichiometric NiCrO3

“…Antiferromagnetic (AFM) half metals are additionally characterised by a fully compensated spin which allows spin-polarized current generation without exhibiting external macroscopic magnetic field. 4,5 The lack of stray fields renders these types of materials as perfect candidates for magnetic sensors, probes and memory storage units. Significant effort has been dedicated to the search for antiferromagnetic half metals, particularly those exhibiting the AFM transition near 300K.…”