Spin-Dependent Multichannel Scattering of Electron in a Quantum Wire

A multichannel quantum tunneling of an electron stream through a potential barrier of a thin defect embedded in a quantum wire is theoretically considered. The electrons are also influenced by a magnetic field embedded in a quantum wire. Analytical expressions for the scattering coefficients and the spin polarization coefficient are obtained. It is shown that the electrons are fully polarized independently of other system parameters in certain energy intervals of each tunneling scattering channel. Any given degree of polarization can be obtained by controlling the energy spectrum with the use of a magnetic field.