Some materials can be self-thermometers at the nanoscale
M. Mecklenburg et al/Science
To take the temperature of very small things, scrap the thermometer. Aluminum, silicon and other materials can serve as their own thermometers, researchers report in the Feb. 6 Science, enabling temperature readings of objects nanometers in size.
The researchers probed the temperature at various points on a tiny aluminum wire by measuring electrons that were fired through the wire. The electrons’ energies exposed subtle changes in the aluminum’s density, which corresponds to the temperature. If the technique passes further scrutiny — and not everyone believes it will — it could be used to measure the temperature of individual transistors.
Temperature, which is related to the energy distribution of particles in a substance, is typically deduced indirectly by measuring another property. In the macroscopic world, that’s pretty easy to do: A bulb thermometer, for example, infers