Electronic Structure Reconstruction by Orbital Symmetry Breaking in IrTe₂

Abstract

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