Advanced applications I: Complex systems
In the first section, we demonstrate the basic usages of the CT-HYB quantum impurity solvers in the iQIST software package. Now we think that you already know how to solve the single-band Hubbard model. That's great. However, in most instances the realistic models are much more complex than the single-band Hubbard model. For example, the interaction terms are rotationally invariant, instead of density-density type. The interaction could even be frequency-dependent. The orbital degeneracy may be broken by the spin-orbital coupling, crystal field splitting, and magnetic etc. The iQIST software package can deal with these issues quite well. In this section, we will teach you how to solve the above problems.