arXiv subjects

M. Kitatani

Publications and source records attributed to M. Kitatani.

2 recordsLinked to original sources

arXiv2025

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

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.

cond-mat.str-el↗

arXiv2018

Quantum criticality in the two-dimensional periodic Anderson model

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 $\gamma\!=\!2$ for the antiferromagnetic susceptibility. At higher temperatures, we have free spins with $\gamma\!=\!1$ instead, whereas at lower temperatures, there is an even stronger increase and suppression of the susceptibility below and above the quantum critical point, respectively.

cond-mat.str-el↗