A B S T R A C T The spin filtering ability of lead/poly-BIPO/lead model junction is investigated. A polaron excitation is considered at the center of polymer. Four polaron types are assumed as the spin and charge density distributions. The Su-Schrieffer-Heeger (SSH) Hamiltonian is modified by Hubbard and Heisenberg Hamiltonians to include the spin and charge interactions. The spin-oriented currents and spin-polarization ability of the model, in the presence/absence of polaron excitations are examined. We find that the complete spin-polarization for both of the excited and non-excited systems is possible and for a given voltage range it is a 100% plato. Our results predict that in the presence of polaron excitations the spin-oriented current is enhanced.

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