Coulomb Frustrated Phase Separation in Quasi-Two-Dimensional Organic Conductors on the Verge of Charge Ordering

TL;DR

This paper investigates Coulomb frustrated phase separation in quasi-2D organic conductors near charge ordering, revealing a mechanism for spatial inhomogeneity driven by quantum critical phenomena within an extended Hubbard model.

Contribution

It introduces the concept of Coulomb frustrated phase separation in a 2D Hubbard model, linking it to charge ordering and spatial inhomogeneity in organic conductors.

Findings

Coulomb frustrated phase separation occurs at nonzero temperatures.

Spatial inhomogeneity with slow relaxation is generated.

The phenomenon is connected to charge ordering quantum criticality.

Abstract

On the basis of an analysis of a 3/4-filled two-dimensional (2D) extended Hubbard model under the fluctuation-exchange approximation, we find Coulomb frustrated phase separation (PS) in a region of nonzero temperature, where the quantum critical phenomenon of charge ordering (CO) dominates. In quasi-2D organic conductors on the verge of CO, this frustrated PS provides a mechanism for generating spatial inhomogeneity, which is characterized by an extremely slow relaxation and an intermediate length scale.