Dear Abbout, Thanks for your reply. The idea was to evaluate green's function for two particular slices of the system I basically followed this discussion: https://rb.gy/v6bkpo Which says to add zero self energy to obtain green's function everywhere. So my next question is if I don't give zero self energy won't my Green's function depend on the choice of Gamma?
I think the other issue is that I am not 100% sure about how to read the output of the greens_function(syst,energy).
