Abstract
We report a photoemission and x-ray absorption study on a ( and 0.35) triangular lattice in which superconductivity is induced by Pt substitution for Au. Au and Te core-level spectra of suggest a valence state of (), which is consistent with its distorted crystal structure with Te-Te dimers and compressed octahedra. On the other hand, valence-band photoemission spectra and preedge peaks of the Te absorption edge indicate that Au bands are almost fully occupied and that Te holes govern the transport properties and the lattice distortion. The two apparently conflicting pictures can be reconciled by strong Au /Au –Te hybridization. The absence of a core-level energy shift with Pt substitution is inconsistent with the simple rigid band picture for hole doping. The Au core-level spectrum gets slightly narrow with Pt substitution, indicating that the small Au charge modulation in distorted is partially suppressed.
- Received 1 July 2014
- Revised 9 October 2014
DOI:https://doi.org/10.1103/PhysRevB.90.144515
©2014 American Physical Society