Hello Antônio,

So here is what I want to do. I have a system where I have defined two lattices, lat_up and lat_down, and they overlap spatially (instead of using matrices in the voltage and hopping, so that it is easier to obtain spin-resolved data). They are defined like this:

lat_up = kwant.lattice.general([(a,a),(a,-a)],[(0,0),(a,0)], name='up')

A_up, B_up = lat_up.sublattices

lat_down = kwant.lattice.general([(a,a),(a,-a)],[(0+d,0),(a+d,0+d)], name='down')

A_down, B_down = lat_down.sublattices

I want to calculate the trace of the dot product between sigma_z and the spinor psi = (psi_up psi_down), and plot it over the system.  That is H(lat_up(i,i)) – H(lat_down(i,i)).

This was easy to do, when I used matrices for spin, but now that I have implemented it using two lattices instead I don’t know how to do it. If I use the same approach as before, I get two values for each (spatial) lattice point, and the result looks completely random.

I hope my explanation was understandable.

Best,

Camilla