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Analysis of charge transfer mechanism on (Ba1-xNdxCuO2+d)2/(CaCuO2)n superconducting superlattices by thermoelectric power measurements

M. Putti·D. Marre·I. Pallecchi·P. G. Medaglia·A. Tebano·G. Balestrino
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Abstract

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.

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M. Putti, D. Marre, I. Pallecchi, P. G. Medaglia, A. Tebano, G. Balestrino. 2004-02-12. Analysis of charge transfer mechanism on (Ba1-xNdxCuO2+d)2/(CaCuO2)n superconducting superlattices by thermoelectric power measurements. https://doi.org/10.1103/physrevb.69.134511

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