Normal metal-high T-c superconductor point contact properties at millimeter waves

Experimental results of the response of a metal-high T-c superconductor (BS CCO-2212) point contact to millimeter wave radiation both at room and liqui d nitrogen temperatures are! presented. Measurements were carried out with and without bias current. An unexpectedly large response signal was observe d when the bias current was applied. This effect is explained by the heatin g of the interface area below the tip of the metallic probe by the alternat ing current of the millimeter wave. The response signal was compared with t hat obtained using a Schottky diode.