Supercurrent distributions and flux penetration in YBa2Cu3O7–YBa2C o0.15Cu2.85O7–YBa2Cu3O7 edge junctions

We report the measurement and analysis of critical current (Ic) modulation and microwave response in magnetic field for a set of YBa2Cu3O7-YBa2Co0.15Cu2.85O7-YBa2Cu 3O7 ramp-edge Josephson junctions. These junctions have been fabricated with various widths w to span the transition from the moderately small (w 2λJ) junction limit at 77 K. As w increases, both the Ic modulation and microwave absorption behavior independently suggest a growing contribution from edge supercurrents. The addition of a superconducting ground plane was shown to reduce the edge supercurrent effects.

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