Researchers have developed a technique using light pulses to create atomic mirrors for enhanced quantum sensors. This new approach uses carefully engineered light pulses as atomic mirrors to cut noise and sharpen quantum measurements.
There’s a big difference between regular and quantum sensors. The former relies on classical physics to measure properties like temperature, pressure, or motion. However, their measurements are affected by factors like thermal noise, material quality, and environmental disturbances.
Quantum sensors, on the other hand, use quantum effects—such as atoms behaving as waves or being in multiple states at once, allowing them to detect even the tiniest changes in physical quantities with much higher precision.
For example, an atomic clock (a quantum sensor) is far more accurate than a quartz watch (a regular sensor) because it measures time using energy transitions in atoms rather than mechanical vibrations.
The trick to control uncontrollable atoms
In their study, the German researchers shed light on a technique that can contribute to the development of more advanced quantum sensors than those available today. “The technique is particularly important for the latest generation of quantum sensors,” the team said.
Quantum sensors use the wave-like behavior of atoms to measure the acceleration and rotation of objects, such as spacecraft, submarines, or even the Earth’s surface, with great precision.
To work properly, they rely on carefully designed mirrors and beam splitters to control the movement of atoms. However, there could be instances when some atoms reflect in unexpected ways due to flaws in the optical setup or stray light.
These unintended reflections can interfere with the measurements of quantum sensors and reduce their accuracy. The study authors used light pulses as high-velocity atomic mirrors to overcome this challenge.
Using light pulses as atomic mirrors
When an atom encounters a properly tuned light pulse, the interaction can be engineered to either reflect or transmit the atom, much like how an optical mirror reflects certain wavelengths of light while letting others pass.
Light pulses as high-velocity atomic mirrors are tuned such that they interact only with atoms moving at certain velocities.
Atoms that match the required speed and direction are coherently reflected, meaning they bounce back predictably, while atoms moving at unintended velocities do not interact strongly with the pulse and pass through. “This approach reduces the noise in the signal, making the measurements much more precise,” the study authors note.
