David Wineland of the University of Colorado Boulder and Serge Haroche of the Collège de France and the Ecole Normale Supérieure in Paris have won the 2012 Nobel Prize for Physics for their work on quantum optics, which could one day lead to faster computer processors, better telecommunications or more accurate timepieces.
Wineland and Haroche worked independently, approaching the field from different directions. Wineland developed ways to isolate individual ions (electrically charged atoms), measuring their quantum state with photons, while Serge Haroche traps individual photons and measures them with atoms.
While the behaviour of electrical currents or beams of light can be described by the laws of classical physics, those rules no longer apply at the scale of individual atoms, electrons or photons. At that level a new set of rules, the laws of quantum mechanics, come into play - and they're increasingly important as the IT industry moves towards chips so densely packed that only a few atoms or electrons are used to store each bit, and fiber optic communications systems so fast that only a few photons make up each pulse of light.
Researchers had faced a number of challenges in studying quantum phenomena, including difficulty in isolating individual particles of matter or light, and in observing or measuring their quantum behaviour without influencing or destroying it. Wineland and Haroche were the first to solve those problems, taking the first steps towards the creation of a new generation of computers.
When, or even if, such computers will appear on the market is not a question Haroche is ready to answer.
"I don't know," he told reporters at the Royal Swedish Academy of Science, which awards the prizes.
"We do fundamental research. We are studying trying to understand the way things behave at the quantum level," he said, just 20 minutes after learning he had won.
"With a lot of research, the final application is not the one that was foreseen in the first place. It was the case with lasers. It was the case with nuclear magnetic resonance. The manipulation of quantum systems belongs to the same kind of physics," he said.
Lasers, at first limited to applications such as range finding or the creation of holograms, are now found in CD players and long-distance telecommunication, while nuclear magnetic resonance, initially conceived as a way to identify individual atoms based on their magnetic properties, is the basis for the magnetic resonance imaging or MRI scanners used to diagnose many diseases.
"There are a lot of things to learn at the fundamental level and there are so many potential applications it is very hard to see which ones will happen. Maybe some kind of computer, some kind of useful quantum simulations, or some kind of communications," Haroche said of his own research.
As for Wineland's work, that could give rise to clocks 100 times more accurate than today's atomic clocks.
"They can measure gravitational shift with very high precision. The clock could be used to measure anomalies in the gravitational field for geology or earthquake detection," Haroche said.
Wineland and Haroche, both born in 1944, will share the prize of 8 million Swedish krona.