Pinning force scaling and its analysis in the LRE-123 ternary compounds

• Scaling analysis of pinning forces is performed in a variety of NEG-123 superconductors.
• Well-developed scaling is obtained in most samples.
• Adding true nanoparticles as pinning sites brakes the scaling behavior.
• Good fits are obtained using the approach of Dew-Hughes with a strong δTc-pinning contribution.

The pinning force scaling is analyzed for various samples of the ternary compound (Nd,Eu,Gd)Ba2Cu3Ox with different types of additions (211 particles, Ag2O, nanoparticles) and variation of the Nd:Eu:Gd content. As already observed in earlier experiments, a well-developed scaling behavior of the normalized flux pinning force versus the normalized applied field is obtained in all samples studied here in the temperature range 60 ⩽ T ⩽ 95 K. These flux pinning curves are analyzed in detail employing the approaches of Dew-Hughes and Kramer, and also several newer, more elaborated pinning models, which enable to judge about the coexistence of various flux pinning mechanisms operating simultaneously.