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Deconstruction of the Kondo Effect near the AFM-Quantum Critical Point

H. Maebashi·K. Miyake·C. M. Varma
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Abstract

The problem of a spin-1/2 magnetic impurity near an antiferromagnetic transition of the host lattice is solved. The problem is shown to transform to a multichannel problem. A variety of fixed points is discovered asymptotically near the AFM-critical point. Among these is a new variety of stable fixed point of a multichannel Kondo problem which does not require channel isotropy. At this point Kondo screening disappears but coupling to spin-fluctuations remains. Besides its intrinsic interest, the problem is an essential ingredient in the problem of quantum critical points in heavy-fermions.

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H. Maebashi, K. Miyake, C. M. Varma. 2005-04-16. Deconstruction of the Kondo Effect near the AFM-Quantum Critical Point. https://arxiv.org/abs/cond-mat/0501337

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