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arXiv · 0804.3395

Kondo Stripes in an Anderson-Heisenberg Model of Heavy Fermion Systems

Abstract

We study the interplay between the spin-liquid and Kondo physics, as related to the non-magnetic part of the phase diagram of heavy fermion materials. Within the unrestricted mean-field treatment of the infinite-$U$ 2D Anderson-Heisenberg model, we find that there are two topologically distinct non-degenerate uniform heavy Fermi liquid states that may form as a consequence of the Kondo coupling between spinons and conduction electrons. For certain carrier concentrations the uniform Fermi liquid becomes unstable with respect to formation of a new kind of anharmonic "Kondo stripe" state with inhomogeneous Kondo screening strength and the charge density modulation. These feature are experimentally measurable, and thus may help to establish the relevance of the spin-liquid correlations to heavy fermion materials.

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Jian-Xin Zhu, I. Martin, A. R. Bishop. 2008-04-21. Kondo Stripes in an Anderson-Heisenberg Model of Heavy Fermion Systems. https://doi.org/10.1103/physrevlett.100.236403

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