It has been suggested that edge-barrier pinning might cause the critical current density (Jc) in bridged superconducting films to increase. Subsequent work indicated that this edge-barrier effect does not impact bridges larger than 1 μm. However, we provide a theoretical assessment with supporting experimental data suggesting edge-barrier pinning can significantly enhance Jc for bridges of a few microns or even tens of microns thus skewing any comparisons among institutions. As such, when reporting flux pinning and superconductor processing improvements for Jc comparisons, the width of the sample has to be taken into consideration as is currently done with film thickness.

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The critical current density ( c ) of YBa 2 Cu 3 O 7 z films doped with varying flux pinning nanoparticle additions was systematically studied, for applied magnetic fields of = 0-9 T and operation temperatures T = 20-77 K. Films were prepared with pulsed laser deposition by (M YBCO) N multilayer or (YBCO) 1 x M x single-target methods, for different M phases including Y 2 O 3 , Y 2 BaCuO 5 (Y211) green-phase, and BaZrO 3 . Very significant differences of c ( c 20 77 K) were measured for optimized M phase additions, that are difficult to model or predict at present. Multilayer films with Y211 and Y 2 O 3 nanoparticle additions had the highest c (20 77 K) for 4 T, and YBCO+BZO-nanorod samples had the strongest c ( ) for 4 T and 65-77 K, however not for T 50 K.Seemingly unusual c ( T) properties were measured for (BZO YBCO) N multilayer films when compared to YBCO and other doped films; c ( ) was almost the same as YBCO at 77 K, however at 30 K c ( 2 T) had the strongest properties increasing 70% compared to YBCO+nanoaddition films and increasing 400% compared to YBCO.Index Terms-Critical current density, engineering current density, flux pinning, high temperature superconductor, nanoparticle, YBa 2 Cu 3 O 7 x .