Strong magnetic proximity effect in van der Waals heterostructures driven by direct hybridization

The conventional spin proximity effect is normally pictured in terms of a small spin splitting of the bands of a nonmagnetic material, due to exchange coupling to a ferromagnet. In this work, the authors show a different type of proximity mechanism, where only one spin channel in the nonmagnetic material becomes strongly hybridized with the ferromagnet, whereas the other remains unaffected. In the case of graphene coupled to CrI₃, a ferromagnetic insulator, the authors show that the hybridization proximity is both strong and electrically tunable.