Oligothiophene nano-rings as electron resonators for whispering gallery modes

TL;DR

This study investigates oligothiophene nano-wires and rings on gold surfaces, revealing their potential as electron resonators for whispering gallery modes, which could impact quantum-electronics applications.

Contribution

It demonstrates that oligothiophene nano-rings can serve as whispering gallery mode resonators for electrons, highlighting their potential in quantum-electronics.

Findings

Differences in electronic states between linear and cyclic oligomers explained by 1D box models.

Nano-rings act as whispering gallery mode resonators for electrons.

Polythiophene behaves as a ribbon with an effective width, not purely 1D.

Abstract

Structural and electronic properties of oligothiophene nano-wires and rings synthesized on a Au(111) surface are investigated by scanning tunneling microscopy. The spectroscopic data of the linear and cyclic oligomers show remarkable differences which, to a first approximation, can be accounted by considering electronic states confinement to one-dimensional (1D) boxes having respectively fixed and periodic boundary conditions. A more detailed analysis shows that polythiophene must be treated as a ribbon (i.e. having an effective width) rather than a purely 1D structure. A fascinating consequence is that the molecular nano-rings act as whispering gallery mode resonators for electrons, opening the way for new applications in quantum-electronics.