Hello all, In follow-up to a recent question "Numerical precision of smatrix" https://mail.python.org/archives/list/kwant-discuss@python.org/thread/LZ22XL... , I am also having issues with numerical precision and/or convergence of the wave functions inside the scattering region when using the default solver. Specifically, I am calculating tunnel couplings from a lead to a well through a barrier. There are resonances in the density of states at the energies of bound states inside the well, whose linewidth depends on the barrier height. When the resonances become too sharp, the DOS computed by Kwant becomes choppy and loses its well defined resonance characteristics. How can I improve the tolerance/precision of this calculation? The code to compute the DOS would look like this: wfs = kwant.wave_function(sys,energy=energy); wf = wfs(leadNum)[leadBandNum] rho = kwant.operator.Density(sys); density = rho(wf); Thanks, Derek