Local thermometry technique based on proximity-coupled superconductor/normal-metal/superconductor devices

In mesoscopic superconductor/normal-metal/superconductor heterostructures, it is known that the resistance of the normal metal between the superconductors has a strong temperature dependence. Based on this phenomenon, we have developed a type of thermometer, which dramatically enhances our ability to measure the local electron temperature T-e at low temperatures. Using this technique, we have been able to measure small temperature gradients across a micron-size sample, opening up the possibility of quantitatively measuring the thermal properties of mesoscopic devices. (C) 2003 American Institute of Physics.