Controllable spin-polarization using external electric field and spin-inversion in a silicene quantum dot

TL;DR

This paper demonstrates that a silicene quantum dot can function as a controllable spin polarizer, spin inverter, and nearly perfect spin filter by tuning external electric and exchange fields, advancing spintronic device capabilities.

Contribution

It introduces a method to control spin polarization and inversion in silicene quantum dots using external electric and exchange fields, a novel approach in spintronics.

Findings

Silicene quantum dot can polarize electron spins from nearly pure down to up.

The quantum dot can invert the spin of incoming electrons, acting as a spin NOT gate.

In the presence of an exchange field, it functions as a nearly perfect spin filter.

Abstract

It is shown that, for appropriate values of electron energy, the silicene dot can work as a controllable spin polarizer. The spin polarizer can polarize the spin of transmitted electrons from nearly pure down to nearly pure up by changing the strength of an external electric field. Also, for spin polarized incoming electrons, the silicene quantum dot can invert the spin of electrons and can works as a spin inverter or a spin NOT gate. In addition, we investigate the effects of exchange field, induced by ferromagnetic substrate, on electron conductance and show that the silicene quantum dot can act as a nearly perfect spin-filter in the presence of exchange field.