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arXiv · 1308.1903

Generalized Wilson Chain for solving multichannel quantum impurity problems

Andrew K. Mitchell·Martin R. Galpin·Samuel Wilson-Fletcher·David E. Logan·Ralf Bulla
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Abstract

The Numerical Renormalization Group is used to solve quantum impurity problems, which describe magnetic impurities in metals, nanodevices, and correlated materials within DMFT. Here we present a simple generalization of the Wilson Chain, which improves the scaling of computational cost with the number of channels/bands, bringing new problems within reach. The method is applied to calculate the t-matrix of the three-channel Kondo model at T=0, which shows universal crossovers near non-Fermi liquid critical points. A non-integrable three-impurity problem with three bands is also studied, revealing a rich phase diagram and novel screening/overscreening mechanisms.

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Andrew K. Mitchell, Martin R. Galpin, Samuel Wilson-Fletcher, David E. Logan, Ralf Bulla. 2014-03-13. Generalized Wilson Chain for solving multichannel quantum impurity problems. https://doi.org/10.1103/physrevb.89.121105

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