Analysis of dislocations in Y-Ba-Cu-O superconductors

Abstract

Transmission electron microscopy was used to characterize dislocations in Y‐Ba‐Cu‐O superconductors. Dislocations which are rarely seen in the sintered YBa₂Cu₃O_7−δ superconductor are found to be abundant in grain‐oriented samples fabricated by the melt‐textured growth method. The density of dislocations is estimated to be about 10⁹ –10¹⁰ lines/cm², which is 2–3 orders of magnitude increased over that for the sintered sample. An analysis using the ḡ⋅b̄=0, 1, and 2 criteria unambiguously proves that the Burgers vectors of the dislocations are of [100] or [010] type with the slip occuring on the (010), (100), or (001) plane. These results imply the possibility of using slip deformation to increase the defect density and influence the flux pinning behavior.