The new thermometer developed by a team of physicists from the Institute for Photonics and Advanced Detection at the University of Adelaide in Australia is three times more sensitive than the most advanced one built to date.
As indicated in a study published in the journal Physical Review Letters , with this instrument they have been able to measure temperatures with an accuracy of 30,000 millionths of a degree in a second . “We believe that it is the best record obtained in history at room temperature,” says Professor of Experimental Physics Andre Luiten, who has coordinated the trial. This clarifies that it is even possible to make more accurate measurements in a cryogenic environment, close to absolute zero (-273.15 ºC).
These experts emphasize that the tool, which uses light to determine temperature, is so powerful that it allows observing fluctuations in matter, whose intimate structure is always in motion on a microscopic scale.
The device inserts two beams of light, one red and one green, into a highly polished crystalline disk . Depending on the temperature at which it is, the rays move at different speeds.
“When we heat it up, the red light slows down slightly compared to the green light,” explains Luiten. “If we force the light to circulate thousands of times around the edge of the disk, we can measure these minute differences with great precision.”
In essence, this technique could be adjusted to determine pressure or humidity, and even used to detect the presence of certain chemical compounds. “This versatility could revolutionize numerous technologies with medical or industrial applications,” Luiten highlights.
