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A Study of the Measurement of Seebeck Coefficient of SiGeIn 1821 German Physicist Thomas J. Seebeck discovered that heat could be converted into electricity when a temperature difference was applied across two points on a material. Theoretically, the generated voltage has a directly proportional relationship with the temperature difference. This relationship is the Seebeck coefficient that scientists always referred to when determining the efficiency of a thermoelectricity convention. In our experiments, however, hysteresis loops appeared when we plotted voltage against temperature difference, and the measured Seebeck appeared differently when the measurements were run under vacuum, air, and helium gas. Measurements were done by using a low-frequency AC measuring method. By simulating the experimental setup into a; thermal circuit, we found that the loop and inconsistency in measuring Seebeck coefficient could be explained by studying the behaviors of a RC circuit in a thermal sense. Under vacuum, the gap of the hysteresis loop can be largely eliminated if the time period of the temperature difference increased up to 4800s. The trend of the variations in measuring Seebeck coefficients in different environments can also be predicted by using different thermal circuit models.
Document ID
Document Type
Conference Paper
Heung, King Yi
(California Inst. of Tech. Pasadena, CA, United States)
Date Acquired
August 23, 2013
Publication Date
August 1, 2005
Publication Information
Publication: Summer Student Research Presentations
Subject Category
Fluid Mechanics And Thermodynamics
Distribution Limits
Work of the US Gov. Public Use Permitted.

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