Josephson junctions and superconducting field effect transistors based on epitaxial Bi2Sr2Can-1CunO2(n+2) thin films

Josephson junctions based on thin films of the Bi2Sr2Ca2Cu3O10 + delta comp ound show IcRn products compatible with YBa2Cu3O7 - delta samples. Using qu asiparticle tunneling experiments we found evidence for a superconductor-in sulator-superconductor tunneling process via localized states in the barrie r. The Bi2Sr2CaCu2O8 + delta compound is investigated regarding possible ap plications in superconducting field effect devices. We present thin films o f four unit cells thickness that are superconducting at 58 K. An inverted m etal-insulator-superconductor structure was prepared. From the modulation o f the normal slate resistance we estimate a carrier density of 7 x 10(19) c m for a superconducting sample. The shift of the transition temperature was 1 K/V. The modulation of the I-V characteristics was demonstrated. (C) 199 9 Elsevier Science Ltd. All rights reserved.