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arXiv · 2203.15475

Continuous ferromagnetic quantum phase transition on an anisotropic Kondo lattice

Jialin Chen·Jiangfan Wang·Danqing Hu·Yi-feng Yang
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Abstract

Motivated by the recent discovery of ferromagnetic quantum criticality in the heavy fermion compound CeRh$_6$Ge$_4$, we develop a numerical algorithm of infinite projected entangled pair states for the anisotropic ferromagnetic Kondo-Heisenberg model in two dimensions and study the ferromagnetic quantum phase transitions with varying magnetic and hopping anisotropy. Our calculations reveal a continuous ferromagnetic quantum phase transition in the large anisotropic region and first-order quantum phase transitions for smaller anisotropy. Our results highlight the importance of magnetic anisotropy on ferromagnetic quantum criticality in Kondo lattice systems and provide a possible explanation for the experimental observation in CeRh$_6$Ge$_4$ with a quasi-one-dimensional magnetic structure. Our work opens the avenue for future studies of the rich Kondo lattice physics using state-of-the-art tensor network approaches.

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Jialin Chen, Jiangfan Wang, Danqing Hu, Yi-feng Yang. 2022-03-29. Continuous ferromagnetic quantum phase transition on an anisotropic Kondo lattice. https://doi.org/10.1103/physrevb.106.075114

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