Using c-axis-oriented oxygen-deficient YBa2Cu3O7-δ film deposited across a low-angle step on a SrTiO3 substrate, we successfully demonstrated intrinsic Josephson effects. In addition to several voltage jumps of large amplitudes (a few millivolts) and remarkable hysteresis on the dc current-voltage curves, we observed upturns on the current-voltage curves under microwave irradiation which appeared at increasingly high voltages with increasing microwave power. We proposed to explain this observation in terms of high-order microwave-induced Shapiro steps.
ASJC Scopus subject areas
- Physics and Astronomy(all)