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arXiv · 1605.06355

Quantum criticality with a twist - interplay of correlations and Kohn anomalies in three dimensions

T. Schäfer·A. A. Katanin·K. Held·A. Toschi
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Abstract

A general understanding of quantum phase transitions in strongly correlated materials is still lacking. By exploiting a cutting-edge quantum many-body approach, the dynamical vertex approximation, we make an important progress, determining the quantum critical properties of the antiferromagnetic transition in the fundamental model for correlated electrons, the Hubbard model in three dimensions. In particular, we demonstrate that -in contradiction to the conventional Hertz-Millis-Moriya theory- its quantum critical behavior is driven by the Kohn anomalies of the Fermi surface, even when electronic correlations become strong.

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T. Schäfer, A. A. Katanin, K. Held, A. Toschi. 2017-06-25. Quantum criticality with a twist - interplay of correlations and Kohn anomalies in three dimensions. https://doi.org/10.1103/physrevlett.119.046402

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