An international team of physicists has created the first fully integrated quantum detector for gravitational waves and dark matter based on the principle of differential atomic interference, which allows for a reduction in noise levels during measurements.
This was announced by the press service of Imperial College London.
Professor Olivier Buchmueller of Imperial College London said in a statement released by the college's press service: "We have taken a major step towards developing large-scale quantum sensors to solve fundamental physics problems. We have been able to demonstrate the feasibility of interfering atoms in the most realistic conditions for making measurements, which opens the way for projects such as the MAGIS detector at Fermi and the AICE facility at CERN (the International Centre for Nuclear Research in Geneva)."
As Professor Büchmueller and his colleagues explained, atomic interferometers are measuring devices that use the quantum properties of atoms to make extremely precise measurements of changes in the position of particles in a vacuum under the influence of various forces, including gravity. These devices rely on special optical traps that capture clouds containing single atoms of cesium, sodium, or strontium and isolate them from the surrounding environment.
During the measurements, scientists manipulate the quantum properties of these atoms so that they begin to behave not as particles, but as waves. By tracking the interactions of these waves with laser beams, the force of gravity can be measured precisely, and other fundamental physical constants can be determined by observing the motion of a quantum particle after it has been released from the trap.
Such measurements have historically been hampered by noise generated by the interaction of the laser beam with clouds of atoms, preventing the detection of dark matter particles or gravitational waves passing through Earth. Professor Büchmueller and his colleagues hypothesized that this noise could be completely suppressed by observing two clouds of atoms simultaneously and calculating the difference between these two measurements.
Guided by this idea, physicists created a prototype differential atomic interferometer based on two clouds of strontium-87 atoms cooled to a temperature of microkelvin (equivalent to -273.1 degrees Celsius).
Subsequent experiments on this device showed that it allows for the measurement of the position of atom drags with the highest possible accuracy permitted by the laws of quantum mechanics, even when artificial distortions are added to the laser beam.
Using this device, researchers were also able to detect artificial vibrations similar in strength and structure to signals produced by gravitational waves or dark matter clusters passing through our planet. This demonstrated for the first time that the American MAGIS detector, currently under construction, and its European counterpart, AICE, planned for development, will be capable of detecting such vibrations originating from astrophysical sources.
