Electronic structure of magnetic semiconductor CdCr_2Te_4: A possible spin-dependent symmetry filter

摘要

We present a theoretical investigation of the electronic and magnetic structure of spinel CdCr_2Te_4 using density functional theory, its extensions via onsite Hubbard U interactions, and a screened-hybrid-functional exchange potential. We find that the ground state is semiconducting within the latter approach, and within this magnetic-semiconducting system, we compute the complex band structure, finding a slowly decaying evanescent △_1 state possibly suitable for realizing a spin-dependent symmetry filter effect.