The mechanism of strain tunable magnetic anisotropy and electronic properties of bilayer CrI3

The bilayer CrI3 is of great interest for spintronics applications due to its unique interlayer antiferromagnetic ordering. In this study, we investigated the phase transition and magnetic anisotropy of bilayer CrI3 under biaxial and uniaxial strains, and found that interlayer magnetic coupling depends crucially on applied strains. The interlayer AFM coupling is enhanced with tensile strain, however, the phase transition point from AFM to FM varies for different compressive strains. Additionally, both stretching and compression lead to a direct to indirect band gap transition due to the horizontal displacement between layers. Finally, perpendicular magnetic easy axis retains for the entire range of strains, arising from iodine (I) atoms in an orbital and site-dependent manner. Our work provides not only application prospects of the bilayer CrI3 but also theoretical effective support for the research and development of the spin electronics and flexible electronics.