The normal-state resistivity of grain boundaries in YBa2Cu3O7−δ

Using an optimized bridge geometry, we have been able to make accurate measurements of the properties of YBa2Cu3O7−δ grain boundaries above Tc. The results show a strong dependence of the change of resistance with temperature on grain boundary angle. Analysis of our results in the context of band bending at the boundary allows us to estimate the height of the potential barrier present at the grain boundary interface.