Magnetic phases of the periodic Anderson model in two dimensions

TL;DR

This study uses advanced tensor network methods to explore magnetic phases in the two-dimensional periodic Anderson model, revealing quantum fluctuation effects and discovering a new antiferromagnetic stripe phase at certain fillings.

Contribution

It applies the iPEPS technique to accurately determine magnetic ground states and uncovers a novel correlated antiferromagnetic stripe phase at non-half-filling.

Findings

Excellent agreement with quantum Monte Carlo at half-filling.

Identification of a new antiferromagnetic stripe phase at n=1.5.

Comparison of quantum fluctuations effects with mean-field predictions.

Abstract

We investigate the ground-state properties of the periodic Anderson model on the square lattice across various band fillings. Employing the infinite projected entangled-pair states (iPEPS) technique, we can determine the magnetic ground states accurately and compare them to mean-field predictions to highlight the effects of quantum fluctuations. At half-filling, we analyze the transition between the antiferromagnetic and paramagnetic (Kondo singlet) phases as a function of hybridization and $f$-level energy, finding excellent agreement with existing quantum Monte Carlo studies in the case of hybridization. For $n = 1.5$ electrons per site, we identify a novel correlated antiferromagnetic diagonal stripe phase as the ground state, which competes with its ferromagnetic partner state.