EVIDENCE FOR LONG LOCALIZATION LENGTH ALONG B-AXIS PRBA2CU3O7 IN A-AXIS YBA2CU3O7 A,B-AXIS PRBA2CU3O7 SUPERLATTICES/

We have investigated resistive transitions of a axis YBa2Cu3O7/a,b axi s PrBa2Cu3O7 superlattices in a magnetic field to study the correlatio n length of vortices along the a axis direction of YBa2Cu3O7 across an a,b axis oriented PrBa2Cu3O7 barrier. The correlation of vortices acr oss up to 480 angstrom of PrBa2Cu3O7 is evidence consistent with long proximity coupling coherence lengths in PrBa2Cu3O7 found in sandwich t ype YBa2Cu3O7/PrBa2Cu3O7/YBa2Cu3O7 Josephson junctions. Investigation of a-b plane and b axis transport of undoped and cobalt doped PrBa2Cu3 O7 films suggests that a long localization length along the b axis of PrBa2Cu3O7 is the origin of this long range proximity coupling.