Equilibrium Fermi-liquid coefficients for the fully screened N-channel Kondo model

Markus Hanl; Andreas Weichselbaum; Jan von Delft; Mikhail Kiselev

doi:10.1103/physrevb.89.195131

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arXiv · 1403.0497

Equilibrium Fermi-liquid coefficients for the fully screened N-channel Kondo model

Markus Hanl·Andreas Weichselbaum·Jan von Delft·Mikhail Kiselev

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Abstract

We analytically and numerically compute three equilibrium Fermi-liquid coefficients of the fully screened $N$-channel Kondo model, namely $c_B$, $c_T$ and $c_\varepsilon$, characterizing the magnetic field and temperature dependence of the resisitivity, and the curvature of the equilibrium Kondo resonance, respectively. We present a compact, unified derivation of the $N$-dependence of these coefficients, combining elements from various previous treatments of this model. We numerically compute these coefficients using the numerical renormalization group, with non-Abelian symmetries implemented explicitly, finding agreement with Fermi-liquid predictions on the order of 5% or better.

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Markus Hanl, Andreas Weichselbaum, Jan von Delft, Mikhail Kiselev. 2014-05-25. Equilibrium Fermi-liquid coefficients for the fully screened N-channel Kondo model. https://doi.org/10.1103/physrevb.89.195131

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