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arXiv · 1210.0573

Heavy antiferromagnetic phases in Kondo lattices

L. Isaev·I. Vekhter
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Abstract

We propose a microscopic physical mechanism that stabilizes coexistence of the Kondo effect and antiferromagnetism in heavy-fermion systems. We consider a two-dimensional quantum Kondo-Heisenberg lattice model and show that long-range electron hopping leads to a robust antiferromagnetic Kondo state. By using a modified slave-boson mean-field approach we analyze the stability of the heavy antiferromagnetic phase across a range or parameters, and discuss transitions between different phases. We also address connection to experiments on heavy fermion compounds.

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L. Isaev, I. Vekhter. 2012-10-01. Heavy antiferromagnetic phases in Kondo lattices. https://doi.org/10.1103/physrevlett.110.026403

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