Amplification of ferromagnetic and transverse transport properties during monolayer-to-bilayer transition in MnSe2: A first-principle study

Transverse anomalous transport properties are highly beneficial for spintronics applications compared with conventional longitudinal transport properties behaviors. Thus, we explore the thickness-dependent anomalous transverse transport properties of mono- and bilayer two-dimensional MnSe₂. Both structures have ferromagnetic ground states with half metallicity. The monolayer structure has a perpendicular magnetic anisotropy of 2.51 meV, and this is increased to 3.57 meV in the bilayer. We find a Curie temperature of 221 K in monolayer MnSe₂, and it reaches 286 K in the bilayer MnSe₂. Despite a relatively small anomalous Hall conductivity (AHC) in the monolayer (−30 S/cm), it is substantially enhanced to −402 S/cm in the bilayer. Due to this enhancement of the AHC, the bilayer MnSe₂ displays a large anomalous thermal Hall conductivity −0.10 W/K.m at 100 K and is further enhanced to −0.2 W/K.m at 200 K. Overall, our study may suggest that the 2D MnSe₂ can be utilized for potential spintronics applications.