Flux-pinnining in Y-0.5/Nd-0.5(123) melt-textured sample

Flux-pinning in Y-0.5/Nd-0.5, (123) melt-textured growth sample that had be en doped with excess 20wt.% Y-1/Nd-1(211) and 0.5 wt.% PtO2 has been analyz ed by means of a scaling approach. The different parameters of scaling, irr eversibility field (B-irr), magnetic field (B-jp) and current density (J(p) ) of the fishtail peak effect, and the field (B-fp) corresponding to the ma ximum pinning force density (F-p,F-max), were determined using the measurem ents of magnetically induced current density as a function of field and tem perature. For the commonly used scaling of normalized volume pinning force, (F-p = J(c)xBa)/F-p,F-max, versus reduced magnetic fields h=B-a/B-irr, (wh ere B-a stands for applied magnetic field), the curves collapse into a univ ersal curve with a peak corresponding to h=0.44. Based on the approach of D ew-Hughes [1], we interpret the position of this peak as a clear indication of a deltaT(c)-pinning type. Similar scaling was also obtained with the us e of B-pf instead of B-irr, but poor scaling was obtained with the use of J (p). Our results are compared with those for other Re (123) systems.