Origin of electronic dimers in the spin-density wave phase of Fe-based superconductors

Maria N. Gastiasoro; P. J. Hirschfeld; Brian M. Andersen

doi:10.1103/physrevb.89.100502

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arXiv · 1307.4913

Origin of electronic dimers in the spin-density wave phase of Fe-based superconductors

Maria N. Gastiasoro·P. J. Hirschfeld·Brian M. Andersen

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Abstract

We investigate the emergent impurity-induced states arising from point-like scatterers in the spin-density wave phase of iron-based superconductors within a microscopic five-band model. Independent of the details of the band-structure and disorder potential, it is shown how stable magnetic (pi,pi) unidirectional nematogens are formed locally by the impurities. Interestingly, these nematogens exhibit a dimer structure in the electronic density, are directed along the antiferromagnetic a-axis, and have typical lengths of order 10 lattice constants in excellent agreement with recent scanning tunnelling experiments. These electronic dimers provide a natural explanation of the dopant-induced transport anisotropy found e.g. in the 122 iron pnictides.

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Maria N. Gastiasoro, P. J. Hirschfeld, Brian M. Andersen. 2013-07-18. Origin of electronic dimers in the spin-density wave phase of Fe-based superconductors. https://doi.org/10.1103/physrevb.89.100502

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