Spin-dependent electron behaviour in quantum point contacts

Abstract

The effect of spontaneous spin polarization in quantum point contacts (QPCs) is investigated by self-consistent modelling within the Kohn-Sham local spin-density formalism. The existence of the spin-polarized state of the QPC channel in the low-density regime is shown to change the value and the shape of the effective potential barrier for up- and down-spin electrons. We suggest that this effect can be relevant to the explanation of the anomalous 0.7-structure in the QPC conductance and may assist spin injection in potential spintronic devices.