Tuning electronic and magnetic properties of armchair|zigzag hybrid graphene nanoribbons by the choice of supercell model of grain boundaries

Abstract

Grain boundaries (GBs) attract much interest for its ability to tune the property of hybrid materials. Theoretically predicting the properties of hybrid graphene with GBs, even a linear GB remains challenging due to its inhomogeneous structure, which makes supercell model tough to choose in theoretic studies. For the first time, the applicability of supercells with different GBs and lattice-mismatches for describing armchair-zigzag hybrid graphene nanoribbons was validated by ab initio molecular dynamic simulations and first principles electronic structure calculations. And to what extent the electronic properties can be tuned by the strain effects resulting from the lattice-mismatch and the GBs distortion in supercells was demonstrated. This work showed that the intrinsic strain in such system plays a decisive role in determining the band structure and spin polarization properties. Hybrid graphene nanoribbon was found to be ferromagnetic in the ground state, especially for the case of using the supercell with nearly-perfect lattice match. Its high Curie temperature suggests the potential applications of this material in spintronics.

Study on magnetic properties of a nano-graphene bilayer

“…Magnetic properties of hybrid graphene are predicted based on molecular dynamic simulations. The hybrid graphene shows ferromagnetic in the ground state and has higher Curie temperature [11]. Monte Carlo simulation has also been employed to study magnetic behaviors of the nano-graphene.…”