PREPARATION AND CHARACTERIZATION OF YBA2CU3O7-DELTA POLYPYRROLE BILAYER STRUCTURES

Electrochemical techniques are exploited to fabricate conductive polym er/high-T-c superconductor bilayer structures. Scanning electron micro scopy, atomic force microscopy, and electrochemical techniques are uti lized to characterize the electrodeposition of polypyrrole layers grow n onto YBa2Cu3O7-delta films. In such hybrid polymer/superconductor sy stems, it is found that, when the polymer is oxidized to its conductiv e state, the transition temperature (T-c) and critical currents (J(c)) of the underlying superconductor film are suppressed. Reversible modu lations of the transition temperatures of up to 50 K are noted for the se structures. Upon reduction df the conductive polymer layer back to its nonconductive form, both T-c and J(c) are found to return to value s close to those acquired for the underivatized YBa2Cu3O7-delta film.