Magnetic Quantum Wire as a Spin Filter: An Exact Study

TL;DR

This paper demonstrates that a magnetic quantum wire can function as an effective spin filter across various bias voltages, using an exact numerical approach based on Green's functions.

Contribution

It introduces a model of a magnetic quantum wire with magnetic and non-magnetic sites as a spin filter, analyzed through an exact Green's function method.

Findings

The quantum wire can selectively filter spins over a wide bias range.

The model provides a basis for fabricating nano-scale spin filters.

Exact numerical results support potential experimental applications.

Abstract

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 are performed numerically which describe two-terminal conductance and current through the wire. Our exact results may be helpful in fabricating mesoscopic or nano-scale spin filter.