Eur. Phys. J. B 5, 457-464 (1998)
https://doi.org/10.1007/s100510050466

Perturbative renormalization of multi-channel Kondo-type models^*

Department of Physics, Tohoku University, Sendai 980-77, Japan

Corresponding author: ^a kuramoto@cmpt01.phys.tohoku.ac.jp

Received: 24 February 1998
Accepted: 17 April 1998
Published online: 15 October 1998

Abstract

The poor man's scaling is extended to higher order by the use of the open-shell Rayleigh-Schrödinger perturbation theory. A generalized Kondo-type model with the SU(n)×SU(m) symmetry is proposed and renormalized to the third order. It is shown that the model has both local Fermi-liquid and non-Fermi-liquid fixed points, and that the latter becomes unstable in the special case of n=m=2. Possible relevance of the model to the newly found phase IV in Ce_xLa_1-xB₆ is discussed.