Wrong signs in the hopping terms in the tutorial
In the tutorial, part 2.3 https://kwant-project.org/doc/1/tutorial/spin_potential_shape the signs in the hopping terms from Rashba Hamiltonian should be opposite, or syst[kwant.builder.HoppingKind((1, 0), lat, lat)]
should be changed to syst[kwant.builder.HoppingKind((-1, 0), lat, lat)]
along with the following explanation.
I believe this important, because this is the first time in the tutorial where the hopping direction matters, and it might teach people to implement hoppings in a wrong way.