Abstract
We present a detailed characterization of the dynamic properties of proximity-coupled Josephson junctions in YBa2Cu3O7 fabricated by electron-beam scribing. A full description of the low-temperature behavior includes nonequilibrium processes in the normal barrier as well as wide-junction effects resulting from the planar geometry. Above ∼40 K these junctions obey the standard (equilibrium) resistively-shunted junction (RSJ) model in applied magnetic field. At lower temperatures, the volt-ampere V(I) curves develop a temperature-dependent "excess critical current," saturating at 0.5-0.75 of the total critical current. Below ∼10 K hysteresis is observed. The observed temperature dependence and magnitude of the excess current and hysteresis are qualitatively consistent with published calculations based on the time-dependent Ginzburg-Landau equations. At low temperatures, the V(I) curves in applied field deviate significantly from the RSJ model, which we attribute to wide-junction behavior with a nonuniform bias-current distribution.
Original language | English |
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Pages (from-to) | 1290-1292 |
Number of pages | 3 |
Journal | Applied Physics Letters |
Volume | 73 |
Issue number | 9 |
DOIs | |
State | Published - 1998 |