AC/DC Transfer Technique for Measuring Thomson Coefficient: Toward Thermoelectric Metrology

We introduce an ac/dc transfer technique for measuring the Thomson coefficient of a metallic sample in high-temperature thermoelectric metrology. The Thomson coefficient is measured by applying equivalent dc and ac to a metallic wire configured similarly to a single-junction thermal converter that is widely used in ac/dc transfer devices. The use of ac/dc makes the expression of the Thomson coefficient simpler than in conventional methods. We describe the measurement principle, the design of the measurement setup, and the experimental results in detail. The experimental results agree closely with those obtained from using a conventional method.