PULSE MEASUREMENT OF THE I-V CHARACTERISTICS IN BI-2212 INTRINSIC JUNCTIONS

Current-voltage (I-V) characteristics are studied in the intrinsic Jos ephson junctions of Bi2Sr2CaCu2Oy single crystals. In order to examine the influence of self-heating, a current pulse (approximate to 0.2 mu sec) is applied to the mesas of 40 mu m phi x 0.15 mu m patterned on the crystal. As a consequence, in contrast to small characteristic vol tage V-c in the continuous-current measurement, the V-c data is found comparable to the BCS value. Moreover, the I-V curve is nearly ohmic f or I>I-c, implying that the nonlinearity under the continuous current is due to heating. The quasiparticle resistance for T<T-c is also pres ented by an estimate from the characteristic voltage.