  We have investigated the charge transfer mechanism in artificial
superlattices by Seebeck effect measurements. Such a technique allows a precise
determination of the amount of charge transferred on each CuO2 plane. A
systematic characterization of thermoelectric power in (BaCuO2+d)2/(CaCuO2)n
and (Ba0.9Nd0.1CuO2+d)2/(CaCuO2)n superlattices demonstrates that electrical
charge distributes uniformly among the CuO2 planes in the Ca-block. The
differences observed in the Seebeck effect behavior between the Nd-doped and
undoped superlattices are ascribed to the different metallic character of the
Ba-block in the two cases. Finally, the special role of structural disorder in
superlattices with n=1 is pointed out by such analysis.
