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

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 ${\hat{I}}^3\approx 1$ for the temperature dependence of the antiferromagnetic susceptibility. We observe a \emph{second} quantum critical behavior with ${\hat{I}}^3=2$ above the continuing zero-temperature magnetic order, at a quantum critical point where the $f$ electrons turn from localized to itinerant.

6+2 pages, 4+2 figures