By monitoring how these giant “Rydberg atoms” interact with heat in their environment, researchers can measure temperature with remarkable accuracy.
The product’s sensitivity could improve temperature measurements in quantum research and industrial manufacturing.
Creating the Rydberg Thermometer
To create this thermometer, researchers filled a vacuum chamber with a gas of rubidium atoms and used lasers and magnetic fields to trap and cool them to nearly absolute zero, around 0.5 millikelvin.
This stopped the atoms from moving. Using lasers, the researchers boosted the atoms’ outermost electrons to high orbits – making them 1,000 times larger than ordinary rubidium atoms.
In Rydberg atoms, the outermost electron is far away from the core of the atom, making it more responsive to electric fields and other influences.
The Role of Blackbody Radiation in Rydberg Atoms
This includes blackbody radiation, the heat emitted by surrounding objects. Blackbody radiation can cause electrons in Rydberg atoms to jump to even higher orbits.
Rising temperatures increase the amount of ambient blackbody radiation and the rate of this process.
Thus, researchers can measure temperature by tracking these energy jumps over time.
Therefore, minor temperature changes could be detected.
Advantages of Rydberg Thermometers
A Rydberg thermometer doesn’t need to be first adjusted or calibrated at the factory because it relies inherently on the basic principles of quantum physics.
Rydberg thermometers also can measure the temperature of their environment from about 0 to 100 degrees Celsius without needing to touch the object being measured.
“We’re essentially creating a thermometer that can provide accurate temperature readings without the usual calibrations that current thermometers require,” said NIST postdoctoral researcher Noah Schlossberger.
Impact on Atomic Clocks and Future Applications
This breakthrough not only paves the way for a new class of thermometers but is particularly significant for atomic clocks because blackbody radiation can reduce their accuracy.
“Atomic clocks are exceptionally sensitive to temperature changes, which can cause small errors in their measurements,” said NIST research scientist Chris Holloway. “We’re hopeful this new technology, using Rydberg atoms, could help make our atomic clocks even more accurate.”
