Understanding the Trade Off between Pinning and Thermal Fluctuations in Determining the Critical Current Density of YBCO Films

It has been theoretically proposed that the critical current density Jc of YBCO should increase monotonically with decreasing effective distance between pinning precipitates (Lc) in the strong three dimensional (3D) pinning regime. However, many times opposite results are observed. This work reveals the complicated interactions between optimizing pinning an