Hi all, Thank you for addressing my previous query. I am trying to plot first few incoming transverse waveguide modes on lead 0. I am wondering whether it is possible to plot all incoming modes on Lead 0. kwant.physics.modes gives me PropagatingModes and Stabilized modes but I want to select just first few modes of incoming flux. Here is the sample code of my system import kwant import numpy as np from matplotlib import pyplot from numpy import sqrt from math import * #====================================================================== # Define the shape ------------------- #====================================================================== def shape(pos): x, y = pos return (np.abs(2.0*x)<=L)&(np.abs(y)<W1/2.0) #---------------------------------------------------------------------- a = 1; t = 1; E0L = 0*t L = 10; # Length of the W1 = 30; # Width on the left # Define geometry -------------------------------------------------------------------------- sys0 = kwant.Builder() lat = kwant.lattice.square(a) #-------------------------------------------------------------------------------------------- # Define onsite energies and couplings ---------------------------------------------------- sys0[lat.shape(wv_shape,(0,0))] = E0 # To make all sites the same sys0[lat.neighbors()] = t #-------------------------------------------------------------------------------------------- # Left lead ---------------------------------------------------------------------------------- left_lead = kwant.Builder(kwant.TranslationalSymmetry([-1,0])) left_lead[(lat(0,y) for y in range(int(-W1/2+1),int(W1/2)))] = E0L left_lead[lat.neighbors()] = t sys0.attach_lead(left_lead); #-------------------------------------------------------------------------------------------- # Right lead --------------------------------------------------------------------------------- right_lead = kwant.Builder(kwant.TranslationalSymmetry([1,0])) right_lead[(lat(0,y) for y in range(int(-W1/2+1),int(W1/2)))] = E0L right_lead[lat.neighbors()] = t sys0.attach_lead(right_lead); #--------------------------------------------------------------------------------------------- sys = sys0.finalized() kwant.plot(sys); def plot_conductance(sys, energies): data = [] for energy in energies: smatrix = kwant.smatrix(sys, energy) data.append(smatrix.transmission(2, 0)+smatrix.transmission(1,2) ) #transmission from left 2 leads to right lead pyplot.figure() pyplot.plot(energies, data) pyplot.xlabel("energy [t]") pyplot.ylabel("conductance [e^2/h]") pyplot.show() energies=[-3+i*0.02 for i in range(100)] plot_conductance(sys,energies)