Tunnel Magnetoresistance of M^(+)@C(subscript 60) (M = Cs, Li, and Na) Molecular Junctions

Abstract

In this research, a theoretical study of spin-polarized quantum transport has been reported through a M^(+)@C(subscript 60) (M = Cs, Li, Na) molecule attached to two square lattice FM electrodes with finite cross sections. The effects of dimerization bond, the contact types, the ion positions into cage and ion types on the transmission coefficient, the spin-injection factor, and the TMR ratio have been investigated using the Keldysh nonequilibrium Green's function formalism. The results indicate that the spin-injection factor can reach to as large as 100% with the proper selection of the contact types, the ion positions and types. When the Li atom locates at 2 A distance from the cage center, the TMR ratio in the Li^(+)@C(subscript 60) molecule varies from 100% to -80% corresponding to the contact types.