Critical Current of Low-Angle Grain Boundaries in High-Tc Superconductors
نویسندگان
چکیده
Dependence of the critical current on the misorientation angle in high-temperature superconductor [001] tilt bicrystal is theoretically examined. We suppose that in the case of relatively small values of the bicrystal misorientation angle θ (θ ≤ 10÷15) the critical current is determined by depinning of vortices, which are locked by edge dislocations aligned along the bicrystal grain boundary. Dependence of the depinning critical current on the misorientation angle is calculated for this case and it reveals a good agreement with experimental data obtained on Y-Ba-Cu-O bicrystals with [001] tilt low-angle grain boundaries.
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