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arXiv · 1205.5102

Breaking of four-fold lattice symmetry in a model for pnictide superconductors

Maria Daghofer·André Fischer
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Abstract

We investigate the interplay of onsite Coulomb repulsion and various mechanisms breaking the fourfold lattice symmetry in a three-band model for the iron planes of iron-based superconductors. Using cluster-perturbation theory allows us to locally break the symmetry between the x- and y-directions without imposing long-range magnetic order. Previously investigated anisotropic magnetic couplings are compared to an orbital-ordering field and anisotropic hoppings. We find that all three mechanisms for a broken rotational symmetry lead to similar signatures once onsite interactions are strong enough to bring the system close to a spin-density wave. The band distortions near the Fermi level are independent of differences between the total densities found in xz and yz orbitals.

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Maria Daghofer, André Fischer. 2012-05-23. Breaking of four-fold lattice symmetry in a model for pnictide superconductors. https://doi.org/10.1088/0953-2048%2F25%2F8%2F084003

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