Pairing on Small Clusters in the Peierls-Hubbard Model: Implications for C$_{60}$

TL;DR

This paper investigates how electron-phonon interactions influence electron pairing in small cluster models of C$_{60}$ within the Peierls-Hubbard framework, highlighting the importance of accurate modeling for understanding superconductivity.

Contribution

It demonstrates the significant impact of electron-phonon coupling on pairing in small clusters and discusses the challenges of extrapolating these results to full C$_{60}$ molecules.

Findings

Electron-phonon interactions can enhance or suppress pairing.

Small cluster calculations require careful interpretation for real C$_{60}$.

Extrapolation pitfalls are identified and discussed.

Abstract

We study the pairing within the Peierls-Hubbard Model for electron- and hole-doped analogs of C$_{60}$ accessible to exact diagonalization techniques (cube, truncated tetrahedron, {\it etc.}). We discuss how inclusion of electron-phonon interactions can substantially modify the conclusions about pairing obtained when this coupling is neglected. We also discuss potential pitfalls in the extrapolation from these small system calculations to C$_{60}$, and stress the necessity of having the correct intuitive picture.