Poor man's scaling equation for the anisotropic Coqblin--Schrieffer model
We derive the poor man's scaling equation to the second order for a general anisotropic model, describing embedded into a gas of itinerant electrons a point scatterer, with its own degrees of freedom. We show how the obtained previously scaling equations for anisotropic $s-d$ exchange model follow from it. We apply the general scaling equation to the anisotropic Coqblin--Schrieffer model. We solve analytically thus obtained poor man scaling equation for that model for the particular case $N=2$. We find the phase, which corresponds to the isotropic Coqblin--Schrieffer model with infinitely strong exchange interaction (the Kondo phase) and the phase with finitely strong Ising interaction.