sciencetech-blog

comments

Scientists have developed the world's most sensitive thermometer capable of measuring temperature to 30 billionths of a degree.

The device, named the nano-Kelvin thermometer, is three times more precise than the best thermometers in existence.

It is so precise that scientists claim they are able to measure the temperature changes of objects as their atoms move around.

The device, named the nano-Kelvin thermometer, forces red and green light to circulate thousands of times around the edge of a disc-shaped crystal. It is so precise that scientists are able to measure the temperature changes of objects as their atoms move around

'We believe this is the best measurement ever made of temperature − at room temperature,' said project leader Professor Andre Luiten from the University of Adelaide.

'To emphasise 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 University of Adelaide claim its device is three times more precise than the best thermometers in existence (stock image used)

According to the journal Physical Review Letters, the technique involves forcing red and green light to circulate thousands of times around the edge of a disc-shaped crystal.

The two colours travel at slightly different speeds, depending on the temperature of the crystal.

'When we heat up the crystal we find that the red light slows down by a tiny amount with respect to the green light,' Professor Luiten said.

'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.'

The technique could be used for ultra-sensitive measurements of other things such as pressure, humidity, force or the concentrations of explosives.

'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.