The effect of the grain boundary plane on transport properties of grain boundaries in YBa2Cu3O6+x

We have investigated the effect of the grain boundary plane on superconducting current transport in 90 deg. [1 0 0] YBa2Cu3Ox grain boundaries. In this work, samples containing a single grain boundary with a unique grain boundary plane were isolated from bulk YBa2Cu3Ox samples. Transport measurements at 77 K showed that while both 90 deg. [1 0 0] twist and symmetric tilt grain boundaries exhibit sensitivity of Jc to small magnetic fields, the symmetric tilt boundaries have a considerably lower zero field Jc and higher grain boundary resistivity, suggesting weaker coupling