Hi Anton,

Happy New Year and hope all is well with you!

Thanks for responding to my inquiry. But I’m still a bit puzzled and I think I might be misunderstanding something very simple.

I ran your code snippet (after cell 7, as you suggested) and got this plot, where the original plots from cell 5 and 7 are simply overlaid, but not overlapping. 

I thought your two plot.spectrum statements are plotting the exact same thing, only difference being one is a discretized version of the other (continuum), and therefore should produce 4 overlapping bands instead of the 8 shown here.  

Do you see what I am missing here? 

Thanks again.

Chagaan

On Dec 28, 2023, at 8:13 PM, Anton Akhmerov <anton.akhmerov@gmail.com> wrote:

Hi Chagaan,

kwant.continuum.discretize doesn't change the scale. Indeed, plotting the two dispersions on the same plot shows that they agree quite well. To confirm, try adding the code below after cell 7. As a note here, the Fermi momentum is around pi/2a, which is rather high, and if one wanted to make a more accurate approximation, reducing the lattice constant would be the way to go.

Best,
Anton

from matplotlib import pyplot as plt

params = dict(
   B_x=0,
   mu=1,
   alpha=0.5,
   Delta=0
)

fig, ax = plt.subplots(figsize=(8, 6))
kwant.plotter.spectrum(h_cont, ('k_x', momenta), params=params, show=False, ax=ax)
kwant.plotter.spectrum(
   infinite_wire,
   ('k_x', np.linspace(-np.pi, np.pi, 301)),
   params=params,
   ax=ax
)