Physics Nobel awarded for macro demonstration of quantum effects
John Clarke, Michel Devoret, and John Martinis honored for work demonstrating quantum mechanical tunneling in electrical circuits
John Clarke of the University of California Berkeley, Michel Devoret of Yale University and UC Santa Barbara, and John Martinis of UC Santa Barbara, were jointly awarded the prize "for the discovery of macroscopic quantum mechanical tunnelling and energy quantisation in an electric circuit", the Royal Swedish Academy of Sciences announced today.
Single particles will sometimes pass through a barrier, a well-known phenomenon in quantum mechanics known as tunneling. In experiments in the 1980s, the Nobel winners demonstrated that this effect can also be seen on a macroscopic scale. In electrical circuits made of superconductors, the researchers showed that groups of electrons, behaving as if they were a single quantum mechanical entity, were able to tunnel across an insulating barrier and produce a voltage. They also showed that the circuit absorbed and emitted discrete packets of energy—the "quanta" that give quantum mechanics its name. In a 1988 Science paper, the Nobelists describe demonstrating the quantum mechanical behavior in an object "big enough to get one's grubby fingers on."