Half-metallic transition for ZGNRs adsorbing porphine molecules under an in-plane external electric field

Abstract

The controlling of magnetic transition behavior by changing the coupling between molecule and nanoribbon has attracted a new topic. Here we study a zigzag graphene nanoribbon (ZGNR) absorbing the porphine molecules with different manners under an in-plane external electric field. These structureless systems may exhibit sensitive magnetic response. By employing the first-principles calculations, we find that the sensitivity of magnetic response for the asymmetry structure model is superior to the symmetry one. In general a series of the magnetic phase transitions for the asymmetry models can be induced by an in-plane external electric filed. Particularly, asymmetrical model of ZGNR absorbing porphine molecule at one side can transfer the half-metallic state from spin-up sub-band to spin-down one. Our analysis demonstrate that the phase transition is manipulated by the direction changing of the interior electric field. Interestingly, the models of structural asymmetry can exhibit spin-polarized electron band structures with the spin-polarization rate reaching up to 100%. The findings may provide an approach for the design of new devices to realize logic operation within spintronics.