Hi, This should work no problem, and it does work for me. Can you attach a full example script that can be run? Thanks, Joe On 22 October 2015 at 23:13, R Mathew <ranchu@gmail.com> wrote:

Hi,

I am trying to simulate a finite size quantum hall strip with periodic boundary in one direction. I am using a modified code from Edx course on Topology in Condensed Matter.

The system hangs when sys.finalized is called.

Is it possible to have periodic system finite system in kwant? I don't want to resort to TranslationalSymmetry in the periodic direction.

Here is the code snippet. # Building system lat = kwant.lattice.square() sys = kwant.Builder()

sys[(lat(x, y) for x in range(L) for y in range(W))] = 4*par.t-par.mu

def hopx(y, par): return -par.t*np.exp(-1j * par.B * y)

for i in xrange(L): for j in xrange(W): if j > 0: sys[lat(i, j), lat(i, j - 1)] = -par.t

# Hopping in x-direction if i > 0: sys[lat(i, j), lat(i - 1, j)] = hopx(j, par)

#Making the system periodic for j in range(W): sys[lat(L-1, j), lat(0, j)] = hopx(j, par)*np.exp(1j * par.phi)

Thanks