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Spectral Density of the Two-Impurity Anderson Model

Satoshi Nishimoto·Thomas Pruschke·Reinhard M. Noack
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Abstract

We investigate static and dynamical ground-state properties of the two-impurity Anderson model at half filling in the limit of vanishing impurity separation using the dynamical density-matrix renormalization group method. In the weak-coupling regime, we find a quantum phase transition as function of inter-impurity hopping driven by the charge degrees of freedom. For large values of the local Coulomb repulsion, the transition is driven instead by a competition between local and non-local magnetic correlations. We find evidence that, in contrast to the usual phenomenological picture, it seems to be the bare effective exchange interactions which trigger the observed transition.

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Satoshi Nishimoto, Thomas Pruschke, Reinhard M. Noack. 2005-11-04. Spectral Density of the Two-Impurity Anderson Model. https://doi.org/10.1088/0953-8984%2F18%2F3%2F015

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