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arXiv · 1812.03821

Quantum criticality in the two-dimensional periodic Anderson model

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

We study the phase diagram and quantum critical region of one of the fundamental models for electronic correlations: the periodic Anderson model. Employing the recently developed dynamical vertex approximation, we find a phase transition between a zero-temperature antiferromagnetic insulator and a Kondo insulator. In the quantum critical region, we determine a critical exponent $γ\!=\!2$ for the antiferromagnetic susceptibility. At higher temperatures, we have free spins with $γ\!=\!1$ instead, whereas at lower temperatures, there is an even stronger increase and suppression of the susceptibility below and above the quantum critical point, respectively.

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T. Schäfer, A. A. Katanin, M. Kitatani, A. Toschi, K. Held. 2019-06-06. Quantum criticality in the two-dimensional periodic Anderson model. https://doi.org/10.1103/physrevlett.122.227201

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