Enhancement of magnetoresistance and current spin polarization in single-molecule junctions by manipulating the hybrid interface states via anchoring groups

Abstract

Abstract Based on density functional theory combined with nonequilibrium Green’s function method, the spin polarization of hybrid interface states in magnetic molecular junctions and their roles in spin-dependent transport are investigated. The results demonstrate that by choosing anchoring atoms with different types of outer orbitals, the spin polarization of the hybrid interface states can be tuned. A dependence of the spin polarization on the atomic electronegativity is revealed, where a high spin polarization is achieved in the case of O atom with large electronegativity. The transport calculation shows that a corresponding adjustable spin-dependent transport is realized, where an enhanced tunneling magnetoresistance and a large spin filtering efficiency are realized by using the anchoring atoms with large electronegativity. This work proposes a valid way to enhance the functionality of molecular spintronic devices by manipulating the hybrid interface states.