Variable temperature scanning laser microscopy reveals current distribution around features in striated superconductor

The objective was to determine if striations in superconducting tapes dictate the current. Variable Temperature Scanning Laser Microscopy, or VTSLM, created two-dimensional maps of voltage during laser heating.; Patterns of two geometries, "zipper" and "brick," were investigated. Striations are intended to limit eddy current and therefore lower AC loss. After three samples were tested, current patterns were evident. First, striations are barriers to current. Second, gaps in the striations have higher voltage than nearby regions. Third, greater current density is evident near gaps in striations, near visible features in material, and where multiple channels merge into one channel. Finally, low critical temperature areas correspond to low critical current areas.; The results of this thesis suggest that striations are barriers to current. Also, VTSLM has proven to be useful for identifying other features that effect current density. Non-destructive performance evaluation of superconducting material may become a new quality-control role for VTSLM.