Using the strong temperature dependent resistance of a normal metal wire in proximity to a superconductor, we have been able to measure the local temperature of electrons heated by flowing a dc current in a metallic wire to within a few tens of millikelvin at low temperatures. By placing two such thermometers at different parts of a sample, we have been able to measure the temperature difference induced by a dc current flowing in the sample. This technique may provide a flexible means of making quantitative thermal and thermoelectric measurements on mesoscopic metallic samples.
@article{arxiv.cond-mat/0105083,
title = {Proximity effect thermometer for local temperature measurements on mesoscopic samples},
author = {J. Aumentado and J. Eom and V. Chandrasekhar and P. M. Baldo and L. E. Rehn},
journal= {arXiv preprint arXiv:cond-mat/0105083},
year = {2009}
}