Thermoelectric size effect in noble metals

The difference between the thermoelectric power of thin foils ranging in size from 2.54×${10}^{-2\mathrm{}}$ to 1.52×${10}^{-3\mathrm{}}$ mm and a 0.254-mm wire of gold, copper, and silver was measured as a function of temperature from 4.2 to 333°K. The electrical resistance of the wire and the foils was measured at 4.2, 77.3, and 296°K. From the high-temperature results values were obtained for ${\left[\frac{\partial \ln l\left(\epsilon \right)}{\partial \ln \epsilon }\right]}_{{\epsilon }_F}$ and ${\left[\frac{\partial \ln A\left(\epsilon \right)}{\ln \epsilon }\right]}_{{\epsilon }_F}$ of - 0.58 ± 0.08 and - 1.00±0.08 for gold, -0.34±0.11 and -1.20±0.11 for copper, and +0.86±0.09 and -1.91±0.09 for silver, respectively. Analysis of the low-temperature results suggest that the thermoelectric size effect can be used to determine subparts per million concentrations of magnetic impurities in the noble metals.