Nano thermometer withstands heat

Researchers need to be able to sense conditions in microscopic environments in order to explore nanotechnology's potential to produce useful machines at the scale of atoms and molecules.

Researchers from the Japanese National Institute for Materials Science (NIMS) have fashioned nano thermometers from a magnesium oxide nanotubes filled with liquid gallium. The tiny thermometers are between 20 and 60 nanometers thick, or about one hundredth the diameter of a red blood cell.

The device has an especially large temperature range for a nanothermometer -- it works up to 1,000 degrees Celsius, or just shy of the melting point of gold. The researchers constructed a thermometer that was able to withstand high temperatures because they used magnesium oxide nanotubes rather than the more common carbon nanotubes.

The thermometers can eventually be used to monitor the temperatures of nano-scale devices like motors. And they have dual use potential -- they can also function as structural elements in nano devices, according to the researchers.

The nano thermometer could be used for practical applications in three to five years, according to the researchers. The work appeared in the August 4, 2003 issue of Applied Physics Letters.