Theoretical study on the quantum well junction CrI3 / CrGeTe3

Abstract

Electronic structure calculations were conducted for the CrI3/CrGeTe3 junction with different separations ( z ) between the two slabs, CrI3 and CrGeTe3, which provide a means to resolve the magneto-volume spin coupling. The calculations demonstrate that high electron mobility, high frequency, and strongly electronic structure modification are obtained at a specific value for slab separation ( z ). z =0.36238, which is equivalent to the insulating separation of 13.85 Å, is preferable for free-to-move carriers, while the spin wave maximum is at z=18 Å. The moment observed in the DOS of the CrI3 layer supports an increase in the surface field, which, in turn, explains the effectiveness of the CrI 3 layer in tunneling applications. The CrI3 Fermi surface contains small electronic pockets derived from the Cr-3d doubly degenerate state at M. The doubly degenerate effective mass 𝒎 ∗ is approximately constant near the bottom of the nearly free electron band, but the triply 𝒎 ∗ increases somewhat at the inflection point by the Cr-3d magnetic field. Depending on the number of d-electrons, the junctions CoMnI3/CrGeTe3, MoI3/CrGeTe3 and WI3/CrGeTe3 are examined. The comparison between CoMnI3, MoI3 and WI3, and CrI3 ensures that the performance of the CrI3 layer is due to the activity of Cr-3d, which provides a unique opportunity to control the junction properties. The DOS shape of the MoI3 layer demonstrates fairly interesting magnetic properties that are nearly similar to those of the CrI3 layer.