Two distinct quantum critical behaviors in the doped two-dimensional periodic Anderson model

M. Kitatani; T. Schäfer; A. A. Katanin; A. Toschi; K. Held

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arXiv · 2503.09529

Two distinct quantum critical behaviors in the doped two-dimensional periodic Anderson model

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

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Abstract

We study quantum criticality in the doped two-dimensional periodic Anderson model with the hybridization acting as a tuning parameter. Employing the dynamical vertex approximation we find two distinct quantum critical behaviors. One is a quantum critical point between the antiferromagnetically ordered and the Kondo state, both metallic with itinerant $f$ electrons. Here, we obtained the critical exponent $\gamma \approx 1$ for the temperature dependence of the antiferromagnetic susceptibility. We observe a \emph{second} quantum critical behavior with $\gamma=2$ above the continuing zero-temperature magnetic order, at a quantum critical point where the $f$ electrons turn from localized to itinerant.

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M. Kitatani, T. Schäfer, A. A. Katanin, A. Toschi, K. Held. 2025-03-12. Two distinct quantum critical behaviors in the doped two-dimensional periodic Anderson model. https://arxiv.org/abs/2503.09529

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