Enhancement of Curie temperature and reorientation of spin in doped Cr2Si2Te6

In this paper, we present the electronic and magnetic properties of the ferromagnetic semiconductor Cr2Si2Te6 doped by charge particles by the first-principles calculations. We find that doped Cr2Si2Te6 manifests a ferromagnetic metallic phase and its Curie temperature significantly increases from 54 to 125 K, as well as the magnetic coupling changing from weak super-exchange to strong double-exchange interaction. Moreover, the magnetic easy axis in doped Cr2Si2Te6 rotates from the ⟨001⟩ direction to the ab-plane. Our results provide an easily accessible method to considerably increase the ferromagnetic transition temperature of van der Waals crystals.