Abstract
We have found a phenomenon that a local area of GeBa2Cu3O7-δ ceramic rod glows with orange once a voltage over a certain value is applied to the rod at room temperature. We named the glowing area as “hot spot”. The hot spot can be expected for the utilization of the functional devices such as a constant current generator, an oxygen sensor, a low-frequency generator and so on. For utilizing the devices, the thermal strength of the rod should be considered. We have found the strength is improved by mixing BaAl2O4 with GdBa2Cu3O7-δ. In this research, characteristics of the composite ceramic rod as the oxygen sensor were investigated.
