Field-controlled quantum anomalous Hall effect in electron-doped CrSiTe$_{ 3 }$ monolayer: a first-principles prediction

Abstract

We report Chern insulating phases emerging from a single layer of layered chalcogenide CrSiTe$_{3}$, a transition metal trichacogenides (TMTC) material, in the presence of charge doping. Due to strong hybridization with Te $p$ orbitals, the spin-orbit coupling effect opens a finite band gap, leading to a nontrivial topology of the Cr $e_{\mathrm{g}}$ conduction band manifold with higher Chern numbers. Our calculations show that quantum anomalous Hall effects can be realized by adding one electron in a formula unit cell of Cr$_{2}$Si$_{2}$Te$_{6}$, equivalent to electron doping by 2.36$\times$10$^{14}$ cm$^{-2}$ carrier density. Furthermore, the doping-induced anomalous Hall conductivity can be controlled by an external magnetic field via spin-orientation-dependent tuning of the spin-orbit coupling. In addition, we find distinct quantum anomalous Hall phases employing tight-binding model analysis, suggesting that CrSiTe$_{3}$ can be a fascinating new platform to realize Chern insulating systems with higher Chern numbers.