Hybridized electronic states in potassium-doped picene probed by soft x-ray spectroscopies

TL;DR

This study investigates the electronic structure of potassium-doped picene using soft X-ray spectroscopies, revealing orbital hybridization and vibronic interactions that are key to understanding its superconductivity.

Contribution

It provides direct experimental evidence of orbital hybridization and vibronic interactions in K-doped picene, advancing understanding of its electronic properties and superconductivity.

Findings

Formation of doping-induced electronic states

Evidence of orbital hybridization near Fermi energy

Presence of Raman-active vibronic interactions

Abstract

The electronic structure of the unoccupied and occupied states of potassium (K)-doped and undoped picene crystalline films has been investigated by using the element-selective and bulk-sensitive photon-detection methods of X-ray absorption and emission spectroscopies. We observed the formation of the doping-induced unoccupied and occupied electronic states in K-doped picene. By applying the inner-shell resonant-excitation experiments, we observed the evidence for the orbital hybridization between K and picene near the Fermi energy. Furthermore, the resonant X-ray emission experiment suggests the presence of the Raman-active vibronic interaction in K-doped picene. These experimental evidences play a crucial role in the superconductivity of K-doped picene.