Backscattered terahertz radiation imaging system to visualize supercurrent distributions

A new type of terahertz (THz) radiation imaging has been proposed and demonstrated. The supercurrent distributions were visualized by detecting the backscattered THz radiation from optically excited high-temperature superconductors. The supercurrent distributions were clearly observed in 100and 500-nm-thick YBa/sub 2/Cu/sub 3/O/sub 7-(delta)/ films in the remanent state. Our system has performance similar to the system with transmission configuration.