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arXiv · 2501.07541

Magnetic phases of the periodic Anderson model in two dimensions

Imre Hagymási
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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.

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Imre Hagymási. 2025-01-13. Magnetic phases of the periodic Anderson model in two dimensions. https://doi.org/10.1103/dh8r-v24r

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