High quality YBa2Cu307 Josephson junctions made by direct electron beam writing
نویسندگان
چکیده
High-T, Josephson junctions have been fabricated by direct electron beam writing over YBa,C&O, thin-tilm microbridges, using scanning transmission electron microscope (STEM) with an accelerating voltage of W-120 kV. Annealing at 330-380 K increases T, and I, of the junctions and makes them more stable. In the operating range of a few degrees below T,, the junctions show 100% magnetic field modulation of the critical current, microwave-induced Shapiro steps oscillating according to the resistively shunted junction (RSJ) model, and RSJ current-voltage characteristics with I$, product up to OS-O.6 mV at 75 K and 0.3 mV at 77 K.
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