Electronic structure of undoped and potassium doped coronene investigated by electron energy-loss spectroscopy

TL;DR

This study uses electron energy-loss spectroscopy to explore how potassium doping alters the electronic structure of coronene, revealing new spectral features and conduction band filling associated with superconductivity.

Contribution

It provides detailed spectroscopic evidence of electronic changes in potassium-doped coronene, advancing understanding of its superconducting properties.

Findings

New peaks in optical gap upon doping

Filling of conduction bands with electrons

Spectroscopic signatures of electronic structure changes

Abstract

We performed electron energy-loss spectroscopy studies in transmission in order to obtain insight into the electronic properties of potassium intercalated coronene, a recently discovered superconductor with a rather high transition temperature of about 15\,K. A comparison of the loss function of undoped and potassium intercalated coronene shows the appearance of several new peaks in the optical gap upon potassium addition. Furthermore, our core level excitation data clearly signal filling of the conduction bands with electrons.