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arXiv · 1606.03536

Spin-Orbit Interactions and the Nematicity Observed in the Fe-Based Superconductors

P. D. Johnson·H. -B. Yang·J. D. Rameau·G. D. Gu·Z. -H. Pan·T. Valla·M. Weinert·A. V. Fedorov
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Abstract

High-resolution angle-resolved photoelectron spectroscopy is used to examine the electronic band structure of FeTe$_{0.5}$Se$_{0.5}$ near the Brillouin zone center. A consistent separation of the $α_{1}$ and $α_{2}$ bands is observed with little $k_{z}$ dependence of the $α_{1}$ band. First-principles calculations for bulk and thin films demonstrate that the antiferromagnetic coupling between the Fe atoms and hybridization-induced spin-orbit effects lifts the degeneracy of the Fe $d_{xz}$ and $d_{yz}$ orbitals at the zone center leading to orbital ordering. These experimental and computational results provide a natural microscopic basis for the nematicity observed in the Fe-based superconductors.

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P. D. Johnson, H. -B. Yang, J. D. Rameau, G. D. Gu, Z. -H. Pan, T. Valla, M. Weinert, A. V. Fedorov. 2016-06-11. Spin-Orbit Interactions and the Nematicity Observed in the Fe-Based Superconductors. https://doi.org/10.1103/physrevlett.114.167001

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