In the past four years there have been many reports of detection of far- infrared radiation in High Temperature Supercondutors1,2. We report here some additional observations of this phenomena, in particular we have measured a threshold of bias-current below which no response is observed to radiation in the range 85-150 cm-1.
K. Schertzl, K. Schertzl,
"FIR response of HTC TI-Ba-Ca-Cu-O films", Proc. SPIE 1576, 16th International Conference on Infrared and Millimeter Waves, 15760C (1 October 1991); doi: 10.1117/12.2297725; https://doi.org/10.1117/12.2297725