Researchers have created the world's most sensitive thermometer that is three times more precise than conventional devices.
"We believe this is the best measurement ever made of temperature - at room temperature," says project leader Professor Andre Luiten, Chair of Experimental Physics in IPAS and the School of Chemistry and Physics, said in a University of Adelaide news release.
"We've been able to measure temperature differences to 30 billionths of a degree in one second," Professor Luiten said. "To [emphasize] how precise this is, when we examine the temperature of an object we find that it is always fluctuating. We all knew that if you looked closely enough you find that all the atoms in any material are always jiggling about, but we actually see this unceasing fluctuation with our thermometer, showing that the microscopic world is always in motion."
The new thermometer uses light to measure temperature; it injects both red and green light into a crystalline disk. The colors travel at different speeds depending on how hot the crystal is.
When the crystal gets hotter the red light tends to slow down compared with the green light.
"By forcing the light to circulate thousands of times around the edge of this disk in the same way that sound concentrates and reinforces itself in a curve in a phenomena known as a 'whispering gallery' - as seen in St Paul's Cathedral in London or the Whispering Wall at Barossa Reservoir - then we can measure this minuscule difference in speed with great precision," Professor Luiten said.
This technique could also be used to create ultra-sensitive devices that measure things such as humidity and pressure.
"Being able to measure many different aspects of our environment with such a high degree of precision, using instruments small enough to carry around, has the capacity to revolutionise technologies used for a variety of industrial and medical applications where detection of trace amounts has great importance," Professor Luiten said
