HI Dominic,

I am using Kwant to stimulate 2D nanowire (square lattice) with two barriers (quite similar to NS junction described in Section 2.6 in the tutorial but topological superconductor is sandwiched between two barriers) and I am measuring the conductance across it using "smatrix.transmission(1, 0)". Somehow in a topological phase, I cannot get zero bias peak to maintain is something wrong with my code? (Checked with spectrum)

You didn't post the code so it's difficult for me to say what the problem may be. I suspect that you may be calculating the conductance incorrectly. You said you used 'smatrix.transmission(1, 0)', however in the presence of the superconductor this transmission will not give you the conductance. I think that you should calculate the conductance in the same way as is shown in tutorial 2.6. Remember to correctly set the 'conservation_law' and 'particle_hole' parameters when constructing the (non-superconducting) leadsso that you can separate out the electron and hole subblocks of the scattering matrix. Post back if something is not clear (or to let us know if this solved your problem). Happy Kwanting, Joe