Thermal spin filtering effect and giant magnetoresistance of half-metallic graphene nanoribbon co-doped with non-metallic Nitrogen and Boron

Ab initio calculations based on density functional theory and non-equilibrium Green's function are performed to investigate the thermal spin transport properties of single-hydrogen-saturated zigzag graphene nanoribbon co-doped with non-metallic Nitrogen and Boron in parallel and anti-parallel spin configurations. The results show that the doped graphene nanoribbon is a full half-metal. The twoprobe system based on the doped graphene nanoribbon exhibits various excellent spin transport properties, including the spin-filtering effect, the spin Seebeck effect, the single-spin negative differential thermal resistance effect and the sign-reversible giant magnetoresistance feature. Excellently, the spinfiltering efficiency can reach nearly 100% in the parallel configuration and the magnetoresistance ratio can be up to -1.5 x 10(10)% by modulating the electrode temperature and temperature gradient. Our findings indicate that the metal-free doped graphene nanoribbon would be a promising candidate for spin caloritronic applications. (C) 2017 Elsevier B.V. All rights reserved.