Electron spin-polarizer on the base of DNA array

Recently, the results of experiment, in which electron flow passing through the array of double-helix DNA molecules become spin-polarized, were reported [1]. In the present work we propose the physical model capable of explaining the spin-polarization effect. The main idea is that the action of elliptic-symmetry parabolic potential (with two different stiffness constants) formed by the array of DNA molecules can polarize the electron flow due to spin-orbital interaction. Our analysis of the Dirac equation for an electron in an elliptic parabolic potential shows that the system of DNA molecules can work as spin-polarizer. We calculate the spin polarization value of the electron flow in dependence of the ratio of parabolic frequencies (stiffness constants) of the potential. This phenomena may be applied for constructing spin-polarizers on the basis on DNA arrays without using any magnetic materials.