  It is now common practice to solve the Schr\"odinger equation to estimate the
tunneling current between two metal electrodes at specified potentials, or the
transmission through a potential barrier by assuming an incident, reflected,
and transmitted wave. However, we suggest that these methods may not be
appropriate for nanoscale circuits. The electron man-free path may be as long
as 68.2 nm in metallic elements so we consider the possibility that quantum
effects may occur throughout a nanoscale circuit, including the connections.
Analytical methods are presented for modeling the coherent transfer of the
wavefunction through a closed circuit.
