Title: One- and two-channel Kondo model with logarithmic Van Hove singularity: a numerical renormalization group solution,
Abstract: Simple scaling consideration and NRG solution of the one- and two-channel
Kondo model in the presence of a logarithmic Van Hove singularity at the Fermi
level is given. The temperature dependences of local and impurity magnetic
susceptibility and impurity entropy are calculated. The low-temperature
behavior of the impurity susceptibility and impurity entropy turns out to be
non-universal in the Kondo sense and independent of the $s-d$ coupling $J$. The
resonant level model solution in the strong coupling regime confirms the NRG
results. In the two-channel case the local susceptibility demonstrates a
non-Fermi-liquid power-law behavior.