article about ferromagnetic coupling in CrI3 - In Brief

Methods Used: Projector augmented wave (PAW) method is a numerical algorithm that is used to perform efficient density functional theory (DFT) calculations. The generalized gradient approximation (GGA) is a method that improves the description of nonuniform electron distributions in molecules, solids, and atoms.

The bilayer CrI3 has interlayer antiferromagnetic coupling. For introduction of dopants O, P, S, As, and Se substitution at the I1(I2) site leads to interlayer ferromagnetism. For C or N doped cases, interlayer antiferromagnetism occurs.

As per study, there is no correlation between the strength of ferromagnetic coupling and the interlayer distance. The interlayer magnetism of vdW materials is closely related to different 3d electron occupation between different layers.

As-doping leads to obvious change of charge distribution inside the interlayer space.

Interlayer ferromagnetic coupling in doped bilayer CrI3 occurs due to formation of localized spin-polarized state. It is a small region where the electron spins are aligned, creating a tiny magnetic area due to something unusual (like a dopant) in the material. This tiny magnetic area can have a big effect on the material’s overall magnetic behavior.

Source: https://link.springer.com/article/10.1007/s11467-024-1435-2#:~:text=Further%20analysis%20shows%20that%20the,can%20realize%20interlayer%20ferromagnetic%20coupling.