# 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…

## 93 Citations

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