LATERAL-TYPE INTRINSIC JOSEPHSON-JUNCTIONS USING Y1BA2CU3O7-DELTA ANDBI2SR2CA1CU2O8+DELTA FILMS

We observed the Josephson effect with hysteretic I-V characteristics o n lateral-type grain boundary junctions using Y1Ba2Cu3O7-delta (YBCO) and Bi2Sr2Ca1Cu2O8+delta(BSCCO) films. In the case of YBCO, grain boun daries consisting of an a-axis oriented needle-like,main surrounded by c-axis oriented grains are used for Josephson junctions. The junction s using as-grown films without annealing did not show hysteretic I-V c haracteristics, but they show RSJ-type I-V characteristics with no hys teresis. after appropriate annealing in pure Ar, this junction propert y changes to have hysteretic I-V characteristics. In the case of BSCCO , grain boundaries consisting of a (110) oriented needle like grain su rrounded by (001) oriented grains sire used. Hysteretic I-V characteri stics are observed for the sample, indicating the presence of the intr insic Josephson effect caused by stacked CuO2 double layers along the c-direction. (C) 1997 Elsevier Science B.V.