Strain induced half-semiconductor to half-metallic transition in 2D magnet CrI₃ : A DFT approach

In this work, compressive and tensile strain (uniaxial as well as biaxial) upto 12% have been applied to study the variation of the electronic and magnetic properties of CrI₃ employing density functional theory in (LDA+U) exchange correlation scheme. The stability limits of the structures under the influence of strains have been carried out via the deformation potential and stress-strain relation. Using appropriate strains, the pristine half-semiconducting nature can be tuned to observe half-metallicity. Further, the indirect band gap in the half-semiconducting phase can be increased by the application of tensile strain. The magnetic moment computed from the density of states is enhanced significantly under the influence of compressive strain. However, it has been observed that after the application of strain in some specific crystal directions, the magnetic moment of monolayer CrI₃ remains almost unchanged. Thus, with the help of strain, the tuned half-metallicity along with underlying characteristic ferromagnetism of this material can unfold a new avenue for potential usage in spintronic devices.