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arXiv · 1611.01822

Quantum critical local spin dynamics near the Mott metal-insulator transition in infinite dimensions

Nagamalleswararao Dasari·N. S. Vidhyadhiraja·Mark Jarrell·Ross H. McKenzie
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Abstract

Finding microscopic models for metallic states that exhibit quantum critical properties such as $\omega/T$ scaling is a major theoretical challenge. We calculate the local dynamical spin susceptibility $\chi(T,\omega)$ for a Hubbard model at half filling using Dynamical Mean-Field Theory, which is exact in infinite dimensions. Qualitatively distinct behavior is found in the different regions of the phase diagram: Mott insulator, Fermi liquid metal, bad metal, and a quantum critical region above the finite temperature critical point. The signature of the latter is $\omega/T$ scaling where $T$ is the temperature. Our results are consistent with previous results showing scaling of the dc electrical conductivity and are relevant to experiments on organic charge transfer salts.

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Nagamalleswararao Dasari, N. S. Vidhyadhiraja, Mark Jarrell, Ross H. McKenzie. 2016-11-06. Quantum critical local spin dynamics near the Mott metal-insulator transition in infinite dimensions. https://doi.org/10.1103/physrevb.95.165105

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