Magnetic Flux Trap in Ion Implanted YBCO Thin Films Diagnosed by Terahertz Mapping

摘要

We studied terahertz (THz) radiation from the magnetic flux trapped YBCO thin films. Artificial trap centers were selectively introduced in the films by an oxygen ion implantation. The two-dimensional THz radiation images observed for the flux-trappe4d films successfully visualized the supercurrent distribution around the trap centers and suggested that the THz radiation from the flux-trapped films originates from the optical modulation of the supercurrent circulating around the trapped magnetic flux. Furthermore the radiation properties had strong dependence on the magnetic flux trap conditions and temperature.