Unconventional superconductivity near a flat band in organic and organometallic materials

TL;DR

This paper investigates electron correlation-driven superconductivity in a decorated honeycomb lattice with a flat band, predicting high critical temperatures and novel pairing symmetries enabled by lattice decoration.

Contribution

It demonstrates the emergence of high-temperature superconductivity with multiple pairing symmetries in a decorated honeycomb lattice featuring a flat band, highlighting the role of lattice decoration.

Findings

Singlet superconductivity with extended-s, extended-d, and f-wave symmetry found

f-wave pairing enabled by lattice decoration

Predicted critical temperature higher than similar lattices without flat bands

Abstract

We study electron correlation driven superconductivity on a decorated honeycomb lattice (DHL), which has a low-energy flat band. On doping, we find singlet superconductivity with extended-s, extended-d and f-wave symmetry mediated by magnetic exchange. f-wave singlet pairing is enabled by the lattice decoration. The critical temperature is predicted to be significantly higher than on similar lattices lacking flat bands. We discuss how high-temperature superconductivity could be realized in the DHL materials such as Rb3TT. 2 H2O and Mo3S7(dmit)3.