Detection properties of slot antenna coupled YBCO microbridges based on vortex motion

High-T_c YBa₂Cu₃O_7-δ (YBCO) microbridges coupled to a slot antenna were fabricated and the video detection properties in the resistive state were investigated under the irradiation of 94 GHz millimeter-waves. A detected voltage dominated by the nonbolometric response due to vortex motion was observed in the vicinity of the critical temperature. From measurements of the polarization dependence of the detected voltage, it was found that the detected voltage, based on the vortex motion, was not due to the photon energy but instead to a high frequency current induced in the antenna. I-V characteristics of the device with and without the external magnetic fields were also measured. Detected voltages increased with the vortex velocity and the maximum detected voltage was obtained when the vortex velocity was at its maximum.