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arXiv · 0808.3788

Nonlinear Sigma Model Analysis of the AFM Phase Transition of the Kondo Lattice

T. Tzen Ong·B. A. Jones
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Abstract

We have studied the antiferromagnetic quantum phase transition of a 2D Kondo-Heisenberg square lattice using the non-linear sigma model. A renormalization group analysis of the competing Kondo -- RKKY interaction was carried out to 1-loop order in the $\epsilon$ expansion, and a new quantum critical point is found, dominated by Kondo fluctuations. In addition, the spin-wave velocity scales logarithmically near the new QCP, i.e breakdown of hydrodynamic behavior. The results allow us to propose a new phase diagram near the AFM fixed point of this 2D Kondo lattice model.

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T. Tzen Ong, B. A. Jones. 2008-08-27. Nonlinear Sigma Model Analysis of the AFM Phase Transition of the Kondo Lattice. https://doi.org/10.1103/physrevlett.103.066405

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