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Numerical renormalization-group study of the Bose-Fermi Kondo model

Matthew T. Glossop·Kevin Ingersent
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Abstract

We extend the numerical renormalization-group method to Bose-Fermi Kondo models (BFKMs), describing a local moment coupled to a conduction band and a dissipative bosonic bath. We apply the method to the Ising-symmetry BFKM with a bosonic bath spectral function $η(ω)\propto ω^s$, of interest in connection with heavy-fermion criticality. For $0<s<1$, an interacting critical point, characterized by hyperscaling of exponents and $ω/T$-scaling, describes a quantum phase transition between Kondo-screened and localized phases. Connection is made to other results for the BFKM and the spin-boson model.

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Matthew T. Glossop, Kevin Ingersent. 2005-08-11. Numerical renormalization-group study of the Bose-Fermi Kondo model. https://doi.org/10.1103/physrevlett.95.067202

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