Photoresponse of shallow step, weak-link bridges using inverted cylindrical magnetron-sputtered Y1Ba2Cu3O7−x thin films

The photoresponse of Y1Ba2Cu3O7−x step, weak-link devices on MgO substrates has been measured using a He-Ne laser light source. The temperature and magnetic-field dependencies of the device critical current density were investigated. Single-step and multistep devices were fabricated and found to have a bolometric response in the resistive region and weak-link, video-detection response in the superconducting region. These devices are suitable for operation over a wide range of temperatures from 4 to 90 K. Responsivities greater than 1000 V/W were measured at low temperature for some devices.