Quantum phase transitions and thermodynamics of the power-law Kondo model

  title={Quantum phase transitions and thermodynamics of the power-law Kondo model},
  author={Andrew K Mitchell and Matthias Vojta and Ralf Bulla and Lars Fritz},
  journal={Physical Review B},
We revisit the physics of a Kondo impurity coupled to a fermionic host with a diverging power-law density of states near the Fermi level, $\rho(\omega) \sim |\omega|^r$, with exponent $-1<r<0$. Using the analytical understanding of several fixed points, based partially on powerful mappings between models with bath exponents $r$ and $(-r)$, combined with accurate numerical renormalization group calculations, we determine thermodynamic quantities within the stable phases, and also near the… Expand
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