Anderson impurity in pseudo-gap Fermi systems

@article{Bulla1997AndersonII,
  title={Anderson impurity in pseudo-gap Fermi systems},
  author={Ralf Bulla and Thomas Pruschke and A. Akylas Imperial College and London and Universitaet Regenburg},
  journal={Journal of Physics: Condensed Matter},
  year={1997},
  volume={9},
  pages={10463-10474}
}
We use the numerical renormalization group method to study an Anderson impurity in a conduction band with the density of states varying as with r > 0. We find two different fixed points: a local-moment fixed point with the impurity effectively decoupled from the band and a strong-coupling fixed point with a partially screened impurity spin. The specific heat and the spin susceptibility show power-law behaviour with different exponents in the strong-coupling and local-moment regimes. We also… 
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