Slot antenna coupled YBa 2Cu 3O 7− δ hot-electron bolometers for millimeter-wave radiation

Abstract

Slot antenna coupled YBa 2Cu 3O 7− δ (YBCO) hot-electron bolometers for 94 GHz millimeter-wave radiation were fabricated. The video detection was carried out in order to investigate response mechanisms of fabricated devices. The bolometric response was dominant at temperatures from the transition region to the normal state. However, the nonbolometric response due to the flux creep was also observed in the vicinity of the critical temperature ( T c). When increasing the bias current, the nonbolometric response was dominant. The mixing property of the device, which was dominated by the bolometric response, was also measured. The YBCO bolometer mixer with the phonon diffusion time of about 0.65×10 −9 s was realized in the heterodyne mixing at 94 GHz.