Renormalization Effects on Quasi-Two-Dimensional Organic Conductor \alpha-(BEDT-TTF)2I3

TL;DR

This paper investigates how long-range Coulomb interactions influence the electronic properties of the quasi-two-dimensional organic conductor -(BEDT-TTF)2I3, revealing velocity enhancement and tilted Dirac cone reshaping through renormalization group analysis.

Contribution

It provides a theoretical analysis of Coulomb interaction effects on -(BEDT-TTF)2I3's low-energy electronic structure using renormalization group methods, highlighting velocity enhancement and susceptibility predictions.

Findings

Logarithmic velocity enhancement near the Fermi level

Reshaping of tilted Dirac cones due to interactions

Predicted site-selective spin susceptibility measurable by NMR

Abstract

The quasi-two-dimensional organic semiconductor \alpha-(BEDT-TTF)2I3 [BEDT-TTF=bis(ethylenedithio)tetrathiafulvalene] has an anisotropic linear dispersion with a zero energy gap near the Fermi level. Owing to the vanishing density of states at the Fermi level, the Coulomb interaction is unscreened in this material. We theoretically study the effect of the long-range Coulomb interaction and the low-energy/long-wavelength behavior of \alpha-(BEDT-TTF)2I3 using the renormalization group analysis. The nearly logarithmic enhancement of the velocity reshapes tilted Dirac cones, and changes the low-temperature behavior. We also show the theoretical calculation for the site-selective spin susceptibility, which can be measured in an NMR experiment.