Insight into interlayer magnetic coupling in 1 T -type transition metal dichalcogenides based on the stacking of nonmagnetic atoms

The interlayer coupling in two-dimensional (2D) magnetic materials is significantly important in determining the properties of 2D materials and applications of related devices. However, the mechanism that determines the interlayer magnetic coupling has only been comprehensively studied in Cr I₃ and that of transition metal dichalcogenides is still blurred. In this work, through first-principle calculations, we find in 2D magnetic bilayer that the interlayer magnetic coupling is determined by the stacking order of interlayer nonmagnetic atoms, accompanied by the transition between half metal and semiconductor in Mn S₂ . The nonmagnetic atoms bridge the interlayer coupling and the stacking order of nonmagnetic atoms determines the interlayer coupling by altering the interlayer p_z-orbital bonding. Adjusting the structure of interlayer nomagnetic atoms by biaxial strain can also tune the interlayer coupling. The perspective proposed in our work, from the stacking order of nonmagnetic atoms, to understand the interlayer magnetic coupling is also applicable in other 2D materials.