Superconductor superlattice model for small-angle grain boundaries in Y-Ba-Cu-O

The measured critical current ratios of small-angle Y-Ba-Cu-O grain boundaries fabricated by Dimos et al., are calculated from a superconducting superlattice model where the periodicity is given by the Read-Shockley formula. The layers' thicknesses are estimated from stress-field calculations of a periodic edge-dislocations array model. The measured critical current dependence on the misalignment angle and the temperature are reproduced with a single fitting parameter. This parameter is related to the stress field in proximity to an edge dislocation. The model's validity and comparison with other attempts at the same data are discussed