A new pulse method for determining transport critical current of superconducting films

Abstract A new pulse method has been elaborated to solve the problems associated with the measurement of transport critical current in high-T c superconductors. This process results in higher sensitivity and accuracy compared with conventional techniques. The essence of the determination of the critical current is to measure the harmonics of the voltage drop caused by applied pulses of short duration and low repetition rate. In this paper the principle of the measuring procedure is described and, as an example, the results for superconducting Bi(Pb)SrCaCuO thick films with high critical current densities up to 5000 – 7000 A/cm 2 at 77 K are presented. The results of measurements produced by this method are compared with those from more conventional techniques.