Uncertainty Analysis of the Thermal Bridge Method

Thermal bridge method is widely used in thermal conductance measurements of one-dimensional nanostructures. The studies used by thermal bridge method advances our understanding of one-dimensional nanoscale thermal transport. And many efforts have been made to boost the reliability of the thermal bridge method and improve the measurement sensitivity. In this paper, uncertainty analysis is performed on the thermal bridge measurements of a CNT and a CdSe nanowire. Both the Taylor series method and the Monte Carlo method are used to figure out the propagation of the errors in the direct measurements. Our results show that the uncertainty of the thermal conductance decreases as the thermal conductance of the measured sample decreases, which can be attributed to the increase in the temperature drop on the measured sample. This finding indicates that we can reduce the measurement uncertainty by increasing the measured length of the sample or increasing the Joule heating generated on the heat source.