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

S. R. Hassan·A. Georges·H. R. Krishnamurthy
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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 κ-(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.

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S. R. Hassan, A. Georges, H. R. Krishnamurthy. 2004-10-12. Sound Velocity Anomaly at the Mott Transition: application to organic conductors and V2O3. https://doi.org/10.1103/physrevlett.94.036402

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