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arXiv · 1003.5469

Topological and Transport Properties of Dirac Fermions in Antiferromagnetic Metallic Phase of Iron-Based Superconductors

Takao Morinari·Eiji Kaneshita·Takami Tohyama
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Abstract

We investigate Dirac fermions in the antifferomagnetic metallic state of iron-based superconduc- tors. Deriving an effective Hamiltonian for Dirac fermions, we reveal that there exist two Dirac cones carrying the same chirality, contrary to graphene, compensated by a Fermi surface with a quadratic energy dispersion as a consequence of a non-trivial topological property inherent in the band structure. We also find that the presence of the Dirac fermions gives the difference of sign- change temperatures between the Hall coefficient and the thermopower. This is consistent with available experimental data.

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Takao Morinari, Eiji Kaneshita, Takami Tohyama. 2010-06-15. Topological and Transport Properties of Dirac Fermions in Antiferromagnetic Metallic Phase of Iron-Based Superconductors. https://doi.org/10.1103/physrevlett.105.037203

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