YBa₂Cu₃O_7‐δ Superconducting Step Edge Junction: Modeling and Experimental Validation

Herein, the current–voltage ( I–V ) characteristics of the YBa 2 Cu 3 O 7‐δ (YBCO) superconducting step edge junction (SEJ) are simulated using the resistively and capacitively shunted junction (RCSJ) model with a noise factor that arises due to thermal fluctuations at finite temperatures. The simulated results are compared with the experimental I–V curves of a YBCO SEJ fabricated on MgO (100) substrate. When the I–V curves are simulated using the RCSJ model considering a single junction forming at the step edge, the simulated data do not fit with the experimental data. However, a good fit between the simulated and experimental data is observed when the I–V curves are simulated using the RCSJ model considering two Josephson junctions connected in series. The noise factor is found to increase with increasing temperature. The results confirm that the YBCO SEJ can be modeled by a series combination of two Josephson junctions having different values of critical current.