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Numerical Renormalization Group Study of the O(3)-symmetric Anderson Model

R. Bulla·A. C. Hewson
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Abstract

We use the numerical renormalization group method to study the O(3)-symmetric version of the impurity Anderson model of Coleman and Schofield. This model is of general interest because it displays both Fermi liquid and non-Fermi liquid behaviour, and in the large $U$ limit can be related to the compactified two channel Kondo model of Coleman, Ioffe and Tsvelik. We calculate the thermodynamics for a parameter range which covers the full range of behaviour of the model. We find a non-Fermi liquid fixed point in the isotropic case which is unstable with respect to channel anisotropy.

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R. Bulla, A. C. Hewson. 1997-01-21. Numerical Renormalization Group Study of the O(3)-symmetric Anderson Model. https://doi.org/10.1016/s0921-4526(96)00766-1

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