The pair were honoured for pioneering optical experiments in "measuring and manipulation of individual quantum systems," the Nobel Physics jury said in its citation.

"Their groundbreaking methods have enabled this field of research to take the very first steps towards building a new type of super-fast computer based on quantum physics," it said.

"Perhaps the quantum computer will change our everyday lives in this century in the same radical way as the classical computer did in the last century."

The research has also led to the construction of extremely precise clocks that could become the future basis for a new standard of time, with more than hundred-fold greater precision than present-day caesium clocks, it said.

Haroche, 68, said the award was "fairly overwhelming."

"I was in the street, passing near a bench, and was able to sit down immediately," he told journalists via a live link to Stockholm.

"I was walking with my wife, when I saw the Swedish area code, I realised." "I think we will have champagne," he added.

The two scientists specialise in quantum entanglement, a phenomenon of particle physics that has been proven by experiments but remains poorly understood.