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Singular Effects of Impurities near the Ferromagnetic Quantum-Critical Point

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

Systematic theoretical results for the effects of a dilute concentration of magnetic impurities on the thermodynamic and transport properties in the region around the quantum critical point of a ferromagnetic transition are obtained. In the quasi-classical regime, the dynamical spin fluctuations enhance the Kondo temperature. This energy scale decreases rapidly in the quantum fluctuation regime, where the properties are those of a line of critical points of the multichannel Kondo problem with the number of channels increasing as the critical point is approached, except at unattainably low temperatures where a single channel wins out.

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H. Maebashi, K. Miyake, C. M. Varma. 2002-05-20. Singular Effects of Impurities near the Ferromagnetic Quantum-Critical Point. https://doi.org/10.1103/physrevlett.88.226403

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