Biaxial strain, electric field and interlayer distance-tailored electronic structure and magnetic properties of two-dimensional g-C3N4/Li-adsorbed Cr2Ge2Te6 van der Waals heterostructures

Abstract

Recently, it has been proven that the biaxial strain (ε), electric field (E) and interlayer distance (d) can effectively modulate the electronic structure and magnetic properties of two-dimensional (2D) van der Waals (vdW) heterostructures, which have potential applications in spintronic devices. Here, the electronic structure and magnetic properties of 2D g-C₃N₄/Li-adsorbed Cr₂Ge₂Te₆ vdW heterostructures are investigated using first-principles calculations. Their lattice structures are seriously affected by adsorption combination. With external stimulation, the band gap of the heterostructures changes. The heterostructures are metallic at ε = −6% and −4%, and others are n-type semiconductors, where the band gap is 23 meV at ε = 6%. In addition, the magnetic moments of g-C₃N₄ in the adsorption systems are in the range from 0.029 to 0.226 μ_B. The vdW heterostructures show in-plane magnetic anisotropy (IMA) at ε = −6%, −2% and 6% and perpendicular magnetic anisotropy (PMA) at ε = −4%, 0, 2% and 4%. On applying an electric field and changing the interlayer distance, the vdW heterostructures show PMA. These results are significant to the low-dimensional spintronic devices.