CURRENT DISTRIBUTION IN A PLANAR YBA2CU3O7-DELTA MULTILINE STRUCTURE

The characterization of the current density distribution in an edge-sh aped region of a planar YBa2Cu3O7-delta flux transformer is reported f or the first time. The analysis was performed by means of three-dimens ional computation of the electromagnetic field. In addition, experimen tal studies using low-temperature scanning electron microscopy were ca rried out. It is shown that the current density distribution in edge r egions deviates strongly from the symmetric case, which is established in the case of straight conductors. The results of calculation and me asurement are discussed with respect to consequences for the design of flux transformers for SQUID systems.