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arXiv · 1206.0512

Dirac Fermion in Strongly-Bound Graphene Systems

Yuanchang Li·Pengcheng Chen·Gang Zhou·Jia Li·Jian Wu·Bing-Lin Gu·S. B. Zhang·Wenhui Duan
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Abstract

It is highly desirable to integrate graphene into existing semiconductor technology, where the combined system is thermodynamically stable yet maintain a Dirac cone at the Fermi level. Firstprinciples calculations reveal that a certain transition metal (TM) intercalated graphene/SiC(0001), such as the strongly-bound graphene/intercalated-Mn/SiC, could be such a system. Different from free-standing graphene, the hybridization between graphene and Mn/SiC leads to the formation of a dispersive Dirac cone of primarily TM d characters. The corresponding Dirac spectrum is still isotropic, and the transport behavior is nearly identical to that of free-standing graphene for a bias as large as 0.6 V, except that the Fermi velocity is half that of graphene. A simple model Hamiltonian is developed to qualitatively account for the physics of the transfer of the Dirac cone from a dispersive system (e.g., graphene) to an originally non-dispersive system (e.g., TM).

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Yuanchang Li, Pengcheng Chen, Gang Zhou, Jia Li, Jian Wu, Bing-Lin Gu, S. B. Zhang, Wenhui Duan. 2012-06-04. Dirac Fermion in Strongly-Bound Graphene Systems. https://doi.org/10.1103/physrevlett.109.206802

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