Serge Haroche of France and David J. Wineland of the U.S. shared the
Nobel Prize in Physics for devising clever laboratory experiments that
made it possible to control ghostly quantum particles, an achievement
that many theoretical physicists believed could never be done.
The work has already led to the creation of
clocks more than 100 times as precise as existing cesium clocks. More
important, perhaps, their work has laid the groundwork for a possible
quantum computer, a superfast-machine that—if it ever can be built—would
leave today's speediest computers in the dust.
"Through their ingenious laboratory methods Haroche and Wineland together with their research groups have managed to measure and control very fragile quantum states, which were previously thought inaccessible for direct observation," the Royal Swedish Academy of Sciences said in a news release. The academy awards the Nobel Prize.
Dr. Haroche, born in 1944, is a professor at the Collège de France and École Normale Supérieure in Paris. Dr. Wineland, also born in 1944, is a physicist at the U.S. Department of Commerce's National Institute of Standards and Technology and the University of Colorado in Boulder, Colo.
Quantum particles flit around in a realm that is microscopic and mysterious. You could put two such particles a million miles apart without any direct contact, and yet they can somehow read and affect the properties of each other. Such particles can also exist in several states simultaneously—known as superposition—which is a bit like being in two places at the same time.
Single quantum particles cannot thus be easily separated from their surrounding environment; as soon as they interact with the outside world, they abandon their spooky properties. It's no wonder that in this tenuous world, the possibility of examining, controlling and counting quantum particles had long seemed remote if not impossible.
But Dr. Haroche and Dr. Wineland were able to crack the problem independently, though they approached the challenge in somewhat different ways.
Dr. Haroche controls photons—quantum particles of light—with mirrors. In his Paris lab, photons bounce back and forth between two supercooled, superconducting mirrors for a 10th of a second—a long time in quantum terms.
Dr. Haroche then zaps an atom into this trap.
The interaction between the atom and the photon reveals the presence of
the photon. With the help of some more experimental skulduggery, many
elusive photons can be measured and counted this way, without destroying
them.
At his lab in Boulder, Dr. Wineland traps ions—electrically charged atoms—by surrounding them with electric fields. The experiment is done in an extremely low-temperature vacuum. With the help of a laser, the ion is prodded into a superposition state—two states at one time—and the quantum behavior can thus be studied.
Dr. Wineland's group has used the ion-trap setup to build a clock that is 100 times more accurate than the cesium-based clocks that are currently the standard for measuring time. The ion trap could also be the basis of a quantum computer.
Today's computers encode data in binary digits, ones and zeros. A quantum machine would exploit quantum properties—such as the superposition states—to represent data and for the basis of computing operations. Some very basic calculations using quantum phenomena have already been done.
But there's a huge catch: The quantum information that's the basis for the high-speed calculations has to be isolated from the outside world, so as not to destroy the quantum properties; at the same time, the machine has to somehow communicate and pass on the results of its number-crunching to the outside world.
Based on the experiments of Dr. Wineland and Dr. Haroche, scientists are now trying to figure out how to resolve that paradox.
"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 Royal Swedish Academy of Sciences said.
European Pressphoto Agency
A photo of physicist David J. Wineland from March 2001.
"Through their ingenious laboratory methods Haroche and Wineland together with their research groups have managed to measure and control very fragile quantum states, which were previously thought inaccessible for direct observation," the Royal Swedish Academy of Sciences said in a news release. The academy awards the Nobel Prize.
Dr. Haroche, born in 1944, is a professor at the Collège de France and École Normale Supérieure in Paris. Dr. Wineland, also born in 1944, is a physicist at the U.S. Department of Commerce's National Institute of Standards and Technology and the University of Colorado in Boulder, Colo.
Quantum particles flit around in a realm that is microscopic and mysterious. You could put two such particles a million miles apart without any direct contact, and yet they can somehow read and affect the properties of each other. Such particles can also exist in several states simultaneously—known as superposition—which is a bit like being in two places at the same time.
Single quantum particles cannot thus be easily separated from their surrounding environment; as soon as they interact with the outside world, they abandon their spooky properties. It's no wonder that in this tenuous world, the possibility of examining, controlling and counting quantum particles had long seemed remote if not impossible.
But Dr. Haroche and Dr. Wineland were able to crack the problem independently, though they approached the challenge in somewhat different ways.
Dr. Haroche controls photons—quantum particles of light—with mirrors. In his Paris lab, photons bounce back and forth between two supercooled, superconducting mirrors for a 10th of a second—a long time in quantum terms.
Winners & Their Work
Read more about the 2012 laureates.Nobel Prize Winners
See which academic institutions and countries have had the most winners.At his lab in Boulder, Dr. Wineland traps ions—electrically charged atoms—by surrounding them with electric fields. The experiment is done in an extremely low-temperature vacuum. With the help of a laser, the ion is prodded into a superposition state—two states at one time—and the quantum behavior can thus be studied.
Dr. Wineland's group has used the ion-trap setup to build a clock that is 100 times more accurate than the cesium-based clocks that are currently the standard for measuring time. The ion trap could also be the basis of a quantum computer.
Today's computers encode data in binary digits, ones and zeros. A quantum machine would exploit quantum properties—such as the superposition states—to represent data and for the basis of computing operations. Some very basic calculations using quantum phenomena have already been done.
But there's a huge catch: The quantum information that's the basis for the high-speed calculations has to be isolated from the outside world, so as not to destroy the quantum properties; at the same time, the machine has to somehow communicate and pass on the results of its number-crunching to the outside world.
Based on the experiments of Dr. Wineland and Dr. Haroche, scientists are now trying to figure out how to resolve that paradox.
"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 Royal Swedish Academy of Sciences said.
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