Exact finite-size spectrum for the multi-channel Kondo model and Kac-Moody fusion rules.

Abstract

The finite-size spectrum for the multi-channel Kondo model is derived analytically from the exact solution, by mapping the nontrivial ${\mathit{Z}}_{\mathit{n}}$ part of the Kondo scattering into that for the restricted solid-on-solid model coupled with the impurity. The analysis is performed for the case of n-2S=1, where n is the number of channels and S is the impurity spin. The result obtained is in accordance with the Kac-Moody fusion hypothesis proposed by Affleck and Ludwig.