ELECTROCHEMICAL AND OPTICAL-DEVICES BASED ON MOLECULE HIGH-T-C SUPERCONDUCTOR STRUCTURES

Through the use of electrochemical and vacuum deposition techniques, m olecular materials are combined with high-T-c superconductors in order to fabricate two new classes of hybrid devices. In the first class of devices, electrochemical methods are utilized to deposit polypyrrole onto YBa2Cu3O7-delta structures. With such systems, experiments are co nducted which explore electron transfer events which occur between the conductive polymer and the high-T-c superconductor at temperatures bo th above and below T-c. Here it is found that the transition temperatu re (T-c) of the superconductor is depressed dramatically when polypyrr ole is oxidized to its conductive form and that it returns to a value which is close to the original value upon reduction of the polypyrrole layer to the neutral, nonconductive form. In the second class of devi ces, the ability of molecular dye layers to affect the optical propert ies of YBa2Cu3O7-delta photodetectors is demonstrated. By examining ch anges in the optical and electronic properties of these systems, energ y transfer processes which occur between molecules and high-T-c superc onductors are explored. Here it is found that dye layers are able to a ct as antenna for optical radiation at those wavelengths which the dye layer absorbs light most strongly.