Magnetic quantum wire as a spin filter: An exact study

We propose that a magnetic quantum wire composed of magnetic and non-magnetic atomic sites can be used as a spin filter for a wide range of applied bias voltage. We adopt a simple tight-binding Hamiltonian to describe the model where the quantum wire is attached to two semi-infinite one-dimensional non-magnetic electrodes. Based on single particle Green's function formalism all the calculations which describe two-terminal conductance and current through the wire are performed numerically. Our exact results may be helpful in fabricating mesoscopic or nano-scale spin filter.