Graphene-based half-metal and spin-semiconductor for spintronic applications

In this letter we propose a strategy to make graphene become a half-metal or spin-semiconductor by combining the magnetic proximity effects and sublattice symmetry breaking in graphone/graphene and graphone/graphene/BN heterostructures. Exchange interactions lift the spin degeneracy and sublattice symmetry breaking opens a band gap in graphene. More interestingly, the gap opening depends on the spin direction and the competition between the sublattice asymmetry and exchange field determines the system is a half-metal or a spin-semiconductor. By first-principles calculations and a low-energy effective model analysis, we elucidate the underlying physical mechanism of spin-dependent gap opening and spin degeneracy splitting. This offers an alternative practical platform for graphene-based spintronics.National Natural Science Foundation of China [11204110, 11347005, 11174009]; China 973 Program [2013CB921900, 2012CB921300]; PAPD; Open Fund of Key Laboratory for Intelligent Nano Materials and Devices of the Ministry of Education [INMD-2015M04]SCI(E)EIARTICLEqijingshan@jsnu.edu.cn; hukaige@pku.edu.cn122