The Littlest Hadron Collider
At the Large Hadron Collider in Europe, scientists smash particles together at incredibly high speeds so the nucleus breaks apart and reveals its contents. At Otago University, DWC Principal Investigator Niels Kjaergaard and his team have made a particle collider to peer into the secrets of quantum interactions. The collisions are more subtle but no less revealing than its big European cousin. They use finely tuned laser beams to trap clusters of atoms, cool them down to temperatures just above absolute zero and gently nudge them into each other.
Unlike classical particles which bounce off each other like billiard balls, these atoms sometimes appear to merge and pass through each other like ghosts. At other times they scatter in unexpected directions forming intricate geometries. Sometimes they stick together for a moment forming a kind of short-term molecule before releasing in different directions.
"At these low speeds, the atoms don't break apart. It is the electrons around the outside that interact in a beautiful quantum dance."
This is pioneering work. Niels’ explorations are laying foundations for the extraordinary quantum technologies of the future. Just as Newton and Rutherford discovered the laws of motion and the structure of the atom by pushing and dropping objects and measuring the results, Niels and his team are testing and charting the frontiers of quantum physics. And just as our current technologies, from planes to computers are based on the discoveries of Rutherford and Newton, so will future technologies draw from this foundational research. For example, understanding the way atoms interact at close range could help scientists to understand and improve the performance of high temperature superconductors, which conduct electricity without energy loss due to an unexplained quantum phenomenon.
Niels and his team are currently improving their collider so it can capture two-dimensional grids of atom clusters. These could be used as nodes in photonic devices switched by single quanta of light.
This work could inform the development of unimaginably powerful quantum computers which would revolutionise internet security, drug discovery, astronomy and many other fields.
But for now this is exploration of a new world.