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arXiv · 1902.10111

Au-Ge alloys for wide-range low-temperature on-chip thermometry

J. R. A. Dann·P. C. Verpoort·J. Ferreira de Oliveira·S. E. Rowley·C. J. B. Ford·G. J. Conduit·V. Narayan
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Abstract

We present results of a Au-Ge alloy that is useful as a resistance-based thermometer from room temperature down to at least \SI{0.2}{\kelvin}. Over a wide range, the electrical resistivity of the alloy shows a logarithmic temperature dependence, which simultaneously retains the sensitivity required for practical thermometry while also maintaining a relatively modest and easily-measurable value of resistivity. We characterize the sensitivity of the alloy as a possible thermometer and show that it compares favorably to commercially-available temperature sensors. We experimentally identify that the characteristic logarithmic temperature dependence of the alloy stems from Kondo-like behavior induced by the specific heat treatment it undergoes.

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J. R. A. Dann, P. C. Verpoort, J. Ferreira de Oliveira, S. E. Rowley, C. J. B. Ford, G. J. Conduit, V. Narayan. 2019-02-26. Au-Ge alloys for wide-range low-temperature on-chip thermometry. https://doi.org/10.1103/physrevapplied.12.034024

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