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arXiv · 1309.5210

Evidence for Orbital Order and its Relation to Superconductivity in FeSe0.4Te0.6

Udai Raj Singh·Seth C. White·Stefan Schmaus·Vladimir Tsurkan·Alois Loidl·Joachim Deisenhofer·Peter Wahl
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Abstract

The emergence of nematic electronic states accompanied by a structural phase transition is a recurring theme in many correlated electron materials, including the high-temperature copper oxide- and iron-based superconductors. We provide evidence for nematic electronic states in the iron-chalcogenide superconductor FeSe0.4Te0.6 from quasi-particle scattering detected in spectroscopic maps. The symmetry-breaking states persist above Tc into the normal state. We interpret the scattering patterns by comparison with quasi-particle interference patterns obtained from a tight-binding model, accounting for orbital ordering. The relation to superconductivity and the influence on the coherence length are discussed.

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Udai Raj Singh, Seth C. White, Stefan Schmaus, Vladimir Tsurkan, Alois Loidl, Joachim Deisenhofer, Peter Wahl. 2015-12-09. Evidence for Orbital Order and its Relation to Superconductivity in FeSe0.4Te0.6. https://doi.org/10.1126/sciadv.1500206

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