First-principles study of electric field effect and spin-polarization transport properties of zigzag alpha-2 graphyne nanoribbons

Combining the density functional theory with the non-equilibrium Green's function, we have investigated the external transverse electric field effect of the electronic structures and spin-polarization transport properties within zigzag alpha-2 graphyne nanoribbons (z alpha-2GYNRs). The external transverse electric field can induce remarkable spin-polarized and half-metallicity behaviors in our system when the electric field is lower than 0.4 V/angstrom with the anti-ferromagnetic state. Particularly, we find that a nonmagnetic semiconductor feature can be obtained when the electric field is larger than 0.5 V/angstrom. Furthermore, analyzing the current-voltage characteristics of the z alpha-2GYNRs device, some interesting phenomena such as the excellent spin filtering and negative differential resistance have been found. Our results indicate that the external transverse electric field is a practical method for band modulation of the alpha-2 graphyne, and the design of spin-resolved devices based on z alpha-2GYNRs can realize multifunctional spin-dependent transport features. Published by AIP Publishing.