Substrate induced electronic phase transitions of CrI_{3} based van der Waals heterostructures

Abstract

We perform first principle density functional theory calculations to predict the substrate induced electronic phase transitions of CrI_{3} based 2-D heterostructures. We adsorb graphene and MoS_{2} on novel 2-D ferromagnetic semiconductor—CrI_{3} and investigate the electronic and magnetic properties of these heterostructures with and without spin orbit coupling (SOC). We find that when strained MoS_{2} is adsorbed on CrI_{3}, the spin dependent band gap which is a characteristic of CrI_{3}, ceases to remain. The bandgap of the heterostructure reduces drastically (sim 70%) and the heterostructure shows an indirect, spin-independent bandgap of sim 0.5 eV. The heterostructure remains magnetic (with and without SOC) with the magnetic moment localized primarily on CrI_{3}. Adsorption of graphene on CrI_{3} induces an electronic phase transition of the subsequent heterostructure to a ferromagnetic metal in both the spin configurations with magnetic moment localized on CrI_{3}. The SOC induced interaction opens a bandgap of sim 30 meV in the Dirac cone of graphene, which allows us to visualize Chern insulating states without reducing van der Waals gap.