Anisotropic Kondo Screening in a J=3/2 Impurity Model with Tetragonal Crystal Field

We explore the possibility of anisotropic Kondo screening in generic J =3/2 Kondo and Anderson impurity models with tetragonal crystal fields, using a combination of poor man's scaling and numerical renormalization group (NRG). With these techniques, we can examine the anisotropic screening of the magnetic and orbital susceptibilities at different temperatures and in different model regimes. Notably, we can explore the crossover between SU(4) and SU(2) Kondo physics, which at higher temperatures appears to be mainly driven by anisotropic hybridization rather than the crystal field itself. Our analysis helps establish a correspondence between anisotropic Kondo couplings and experimentally observed temperature scales while developing a better understanding of data obtained from numerical simulations.