  We show that two tight binding electrons that repel may form a bounded pair
in two dimensions. The paired states form a band with energies that scale like
the strength of the interaction potential. By applying an electric field we
show that the dynamics of such states is that of a composite particle of charge
2e. The system still sustains Bloch-like states, so that if the two bands
overlap single and paired states might coexist allowing for a bosonic fluid
component that, if condensed, would decrease the resistance at low
temperatures. The presence of two bands allows for new oscillations whose
experimental detection would permit a direct measurement of the interaction
potential strength.
