Imaging of trapped vortices in YBCO coated conductor by scanning SQUID microscope

Abstract: We investigated trapped vortices in Y1Ba2Cu3O7−δ (YBCO) coated conductor by using a scanning SQUID microscope (SSM). Several peculiar properties of the vortices were observed such as a large bundle of vortices at a certain position and a coexistence of positive- and negative-sign vortices. Comparing the SSM images with that of low temperature scanning laser microscopy (LTSLM) and SEM, we identified the relationship between local dissipation and position of current blocking defect. Furthermore, regular vortex images were also observed by the SSM in the region where higher J c has been identified by the LTSLM. [Copyright &y& Elsevier]