Quantum sensor breakthrough using natural vibrations in artificial atoms

A team of scientists, led by the University of Bristol, has discovered a new method that could be used to build quantum sensors with ultra-high accuracy.

When individual atoms emit light, they do so in discrete packets called photons.

When this light is measured, this discrete or "granular" nature causes particularly small fluctuations in its brightness, because two or more photons are never emitted at the same time.

This property is particularly useful in the development of future quantum technologies, where small fluctuations are essential, and has aroused a renewed interest in technical systems acting as atoms when they emit light, but of which properties are more easily customizable.

These "artificial atoms", as they are called, are generally made from solid materials and are actually much larger objects, in which the presence of vibrations is inevitable and generally considered prejudicial.

However, a collaborative team, led by the University of Bristol, has now established that these natural vibrations in artificial atoms can surprisingly lead to a suppression of brightness fluctuations greater than that present in natural atomic systems.

The authors, who include academics from the universities of Sheffield and Manchester, show that these small fluctuations could be used to build quantum sensors that are intrinsically more accurate than those possible without vibration.

Their findings are published today in the journal Nature Communications.

Dara McCutcheon, a senior research scientist and lecturer in quantum engineering at the University of Bristol's School of Physics, said, "The implications of this research are enormous.

"Usually, one always thinks that the vibrations present in these relatively large artificial atoms are detrimental to the light they emit, because they generally shake the energy levels, the resulting fluctuations being printed on the emitted photons.

"However, what happens here is that at low temperatures, the vibratory environment acts to cool the system, which freezes energy levels and suppresses fluctuations in energy levels. photons emitted. "

This work paves the way for a new vision of these artificial atoms, in which their solid state nature is actually put to good use to produce a light that could not be produced using natural atomic systems .

It also opens the door to a new set of applications that use artificial atoms for enhanced quantum detection, ranging from small-scale magnetometry that can be used to measure signals in the brain, up to detection. large scale gravitational waves revealing cosmic processes. in the center of the galaxies.