Electronic structure reconstruction by orbital symmetry breaking in IrTe2

TL;DR

This study uses ARPES to investigate how lattice distortion in IrTe2 affects its electronic structure, revealing orbital symmetry breaking and Fermi surface reconstruction associated with the phase transition.

Contribution

It demonstrates the orbital symmetry breaking's role in electronic structure reconstruction during the lattice distortion in IrTe2.

Findings

Fermi surface topology changes with distortion

Orbital character influences Fermi surface reconstruction

Lattice distortion affects Ir 5d and Te 5p orbitals

Abstract

We report an angle-resolved photoemission spectroscopy (ARPES) study on IrTe2 which exhibits an interesting lattice distortion below 270 K and becomes triangular lattice superconductors by suppressing the distortion via chemical substitution or intercalation. ARPES results at 300 K show multi-band Fermi surfaces with six-fold symmetry which are basically consistent with band structure calculations. At 20 K in the distorted phase, whereas the flower shape of the outermost Fermi surface does not change from that at 300 K, topology of the inner Fermi surfaces is strongly modified by the lattice distortion. The Fermi surface reconstruction by the distortion depends on the orbital character of the Fermi surfaces, suggesting importance of Ir 5d and/or Te 5p orbital symmetry breaking.