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arXiv · 2108.03835

Schwinger boson approach for the dynamical mean-field theory of the Kondo lattice

Rulei Han·Danqing Hu·Jiangfan Wang·Yi-feng Yang
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Abstract

We apply the dynamical large-$N$ Schwinger boson technique as an impurity solver for the dynamical mean-field theory (DMFT) calculations of the Kondo lattice model. Our approach captures the hybridization physics through the DMFT self-consistency that is missing in the pure Schwinger boson calculations with independent electron baths. The resulting thermodynamic and transport properties are in qualitative agreement with more rigorous calculations and give the correct crossover behavior over a wide temperature range from the local moment regime to the Fermi liquid. Our method may be further extended to combine with the density functional theory for efficient material calculations.

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Rulei Han, Danqing Hu, Jiangfan Wang, Yi-feng Yang. 2021-08-09. Schwinger boson approach for the dynamical mean-field theory of the Kondo lattice. https://doi.org/10.1103/physrevb.104.245132

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