Local singlets, frustration, and unconventional superconductivity in the organic charge-transfer solids

TL;DR

This paper proposes a theory that superconductivity in organic charge-transfer solids arises from a transition from a bond-charge density wave state, modeled by an extended Hubbard Hamiltonian, with implications for experimental observations.

Contribution

It introduces an effective model linking bond-charge density wave order to superconductivity in organic charge-transfer solids, highlighting a new transition mechanism.

Findings

Superconductivity emerges from a bond-charge density wave state.

The extended Hubbard model captures the transition dynamics.

Experimental predictions align with observed behaviors in CTS materials.

Abstract

We suggest that superconductivity (SC) in the organic charge transfer solids (CTS) is reached from a Bond-Charge Density Wave (BCDW). We discuss an effective model for the BCDW to SC transition, an attractive U extended Hubbard Hamiltonian with repulsive nearest neighbor interaction V. We discuss experimental consequences of the theory for different classes of CTS superconductors as well as related inorganic materials.