Every time a new CPU or other computer chip is announced, one of the specs many of us look to is the transistor size. At the moment this is approximately 22 nm, but you can believe companies like Intel and AMD are working to reach smaller sizes. Researchers at University College London however have recently taken a step to the fundamental limit for circuitry, the single-atom limit.
As the name suggests, devices fabricated at the single-atom limit use circuitry just one atom wide. To create these circuits the atoms they are made of will have to be coupled in order for signals to be transported by them. Achieving this coupling has proven difficult though, but the UCL researchers have recently developed a new way to attempt it and have found it to be effective. Using an electron microscope the researchers were able to introduce defects into single silicon atoms, and when these atoms were next to each other, the defects coupled. This coupling caused the defects to take on multiple quantum states, similar to the multiple electron orbitals within a molecule.
This research is likely going to be critical for the development of some quantum computers and for now the researchers are looking at how to reproduce their findings with atoms other than silicon. The researchers are also interested in creating more complicated arrangements of the defects to potentially induce new properties.
Source: University College of London