To measure temperatures around 3,000K, there are few options, such as optical techniques or special thermocouples, with some disadvantages. On the other hand, I am trying to use the noise thermometry technique, with graphite sensors, to generate electrical noise (Johnson Noise), when subjected to an ultr a high temperature, above 2,000K. Could someone help, about where to buy or how to build such graphite sensor (graphite cord)?