PIE in the sky ?
That system itself works by boosting the V in the conductor with the electric field of the laser beam. At the point where the beam enters the conductor, the E field is increased and the current jumps correspondingly. That jump in current doesn't represent creation of charge though, as would be the case in circuits w/o external fields applied.
Before the junction: E = i*V*t = q*V = q*Ebefore_junction*vcharge
After the junction:
E = i*V*t + c*εo*E2 = q*Ebefore_junction*vcharge + c*εo*E2;
The laser just increases the charge velocity at the junction.