kwant.physics.
selfenergy
(h_cell, h_hop, tol=1000000.0)[source]¶Compute the selfenergy generated by the lead.
Parameters:  h_cell : numpy array, real or complex, shape (N,N) The unit cell Hamiltonian
h_hop : numpy array, real or complex, shape (N,M)
tol : float


Returns:  Sigma : numpy array, real or complex, shape (M,M)

Notes
For simplicity this function internally calculates the modes first. This may cause a small slowdown, and can be improved if necessary.