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arXiv · 1101.1055

Numerical Renormalization Group at marginal spectral density: application to quantum tunneling in Luttinger liquids

Axel Freyn·Serge Florens
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Abstract

Many quantum mechanical problems (such as dissipative phase fluctuations in metallic and superconducting nanocircuits, or impurity scattering in Luttinger liquids) involve a continuum of bosonic modes with a marginal spectral density diverging as the inverse of energy. We construct a Numerical Renormalization Group in this singular case, with a manageable violation of scale separation at high energy, capturing reliably the low energy physics. The method is demonstrated by a non-perturbative solution over several energy decades for the dynamical conductance of a Luttinger liquid with a single static defect.

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Axel Freyn, Serge Florens. 2011-05-25. Numerical Renormalization Group at marginal spectral density: application to quantum tunneling in Luttinger liquids. https://doi.org/10.1103/physrevlett.107.017201

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