Sound Velocity Anomaly at the Mott Transition: application to organic conductors and V2O3

TL;DR

This paper models the sound velocity anomaly near the Mott transition using dynamical mean-field theory, explaining experimental observations in organic conductors and predicting similar effects in V2O3.

Contribution

It introduces a simple model within dynamical mean-field theory to explain sound velocity anomalies at the Mott transition, aligning with recent experiments and extending predictions to V2O3.

Findings

Sound velocity shows critical anomalies near the Mott transition.

Model results agree with experiments on organic conductors.

Predicted similar effects in V2O3 despite larger elastic modulus.

Abstract

Close to the Mott transition, lattice degrees of freedom react to the softening of electron degrees of freedom. This results in a change of lattice spacing, a diverging compressibility and a critical anomaly of the sound velocity. These effects are investigated within a simple model, in the framework of dynamical mean-field theory. The results compare favorably to recent experiments on the layered organic \kappa-(BEDT-TTF)_2Cu[N(CN)_2]Cl conductor . We predict that effects of a similar magnitude are expected for V2O3, despite the much larger value of the elastic modulus of this material.