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arXiv · 1702.05460

Shifts and Splittings of the Hole Bands in the Nematic Phase of FeSe

Matthew D. Watson·Amir A. Haghighirad·Hitoshi Takita·Wumiti Mansur·Hideaki Iwasawa·Eike F. Schwier·Akihiro Ino·Moritz Hoesch
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Abstract

We report a high-resolution laser-based angle-resolved photoemission spectroscopy (laser-ARPES) study of single crystals of FeSe, focusing on the temperature-dependence of the hole-like bands around the ${\rm \Gamma}$ point. As the system cools through the tetragonal-orthorhombic "nematic" structural transition at 90~K, the splitting of the $d_{xz}$/$d_{yz}$ bands is observed to increase by a magnitude of 13 meV. Moreover, the onset of a $\sim$10 meV downward shift of the $d_{xy}$ band is also at 90~K. These measurements provide clarity on the nature, magnitude and temperature-dependence of the band shifts at the ${\rm \Gamma}$ point in the nematic phase of FeSe.

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Matthew D. Watson, Amir A. Haghighirad, Hitoshi Takita, Wumiti Mansur, Hideaki Iwasawa, Eike F. Schwier, Akihiro Ino, Moritz Hoesch. 2017-02-17. Shifts and Splittings of the Hole Bands in the Nematic Phase of FeSe. https://doi.org/10.7566/jpsj.86.053703

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