Physicists at the Joint Institute for Laboratory Astrophysics (JILA) have demonstrated the versatility of their newest atomic clock design. Central to its design is the ability to use laser-based “tweezers”, akin to using tractor beams in science fiction, in order to get the best out of its potential performance.
The most striking feature of the new atomic clock is that it operates by using lasers to trap and isolate individual atoms. As described by its official papers, it is essentially an array of 10 strontium atoms, each of which confined within its own separate optical tweezer. The “tweezers” are then produced by diffusing an infrared laser beam into a microscope-like device, separating itself into 10 distinct beams.
Because each atom is separated from one another, interference is almost impossible. Therefore, the atomic clock is always self-correcting each time new sets of atoms are pushed in and out. This results in a near-continuous operation that provides consistently strong signals and high stability.
In fact, all of the major characteristics of this new atomic clock have been previously seen on two of the other well-known atomic clocks. The single-ion quantum logic clock shows strong signal output, while the multi-atom lattice clock also uses the same laser-based method of trapping atoms.
The “tweezer” aspect of the atomic clock is perhaps the most important part of its design. This is because it can offer pinpoint control, allowing the users to adjust the spacing between atoms to “tweak their quantum properties”. Essentially, the beam of light excites the atoms in order to facilitate a charge state, which will then provide a measurement the instrument can use to measure time. In layman’s terms, the atoms are become “fluffy”, so as to make them detectable by a specific means, with the changes made to be measured as a “tick” on the atomic clock.
While ten atoms do seem quite atomic in scale, the next project aims to step this up further by using a set of 150 atoms. Researchers are hopeful that not only would this study eventually bring new milestones to atomic clock design, but would also unlock a few more secrets of the ever-elusive quantum computing realm.
Featured Image credit: JILA/NIST