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arXiv · 0912.0094

Controllability of ferromagnetism in graphene

Tianxing Ma·Feiming Hu·Zhongbing Huang·Hai-Qing Lin
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Abstract

We systematically study magnetic correlations in graphene within Hubbard model on a honeycomb lattice by using quantum Monte Carlo simulations. In the filling region below the Van Hove singularity, the system shows a short-range ferromagnetic correlation, which is slightly strengthened by the on-site Coulomb interaction and markedly by the next-nearest-neighbor hopping integral. The ferromagnetic properties depend on the electron filling strongly, which may be manipulated by the electric gate. Due to its resultant controllability of ferromagnetism, graphene-based samples may facilitate the development of many applications.

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Tianxing Ma, Feiming Hu, Zhongbing Huang, Hai-Qing Lin. 2010-09-15. Controllability of ferromagnetism in graphene. https://doi.org/10.1063/1.3485059

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