For his work, Gabrielse was also awarded the George Ledlie Prize by the President and Fellows of Harvard College, an award given every two years to someone affiliated with the University who has made a contribution to science or “for the benefit of mankind.”

IN THE STILL OF THE LIGHT

This year, several Harvard physicists managed to bring light, which normally travels at 186,000 miles per second, to a stop.

Assistant Professor of Physics Mikhail D. Lukin and Harvard graduate students Michal Bajcsy, Axel P. André and Alexander S. Zibrov, made history when they halted a light pulse for 10 milliseconds.

The result, with significant applications for information processing and the construction of quantum computers, builds on previous experiments, also led by Harvard scientists, which have slowed and briefly stored light.

In 1999, Lene V. Hau, McKay professor of applied physics, supervised an experiment that slowed light to about 40 m.p.h. In 2001, a team led by Lukin and Ronald Walsworth of the Harvard Smithsonian Center for Astrophysics, and independently, a team led by Hau, stopped a light pulse by storing it in the form of excited atoms to be converted back into a light pulse.

“What we have done this year is to actually store the light pulse in electromagnetic form, to actually store the light as light,” Lukin says.

Working in the Lyman laboratory, the researchers used a technique known as electro-magnetically induced transparency, in which they fired a red laser light pulse into a sealed glass cylinder containing rubidium vapor. They fired two control beams through the vapor, rather than the one beam used in previous experiments, so that their interaction simulated the effect of tiny atomic mirrors.

The photons within the light pulse in the vapor bounced back and forth so that the light pulse as a whole was frozen in space.

The study’s findings were published in the December 2003 issue of Nature.

Lukin and his team’s work has significant implications for information processing and quantum communication.

The ability to store and hold a quantum state of light without destroying it is the basis behind the idea of quantum computing.

Light must be in electromagnetic form for individual photons to interact with one another, which allows for information processing.

“The intriguing futuristic application would be processing signals that are carried by individual protons,” says Lukin, who has been on the faculty for three years. “If you could make these single photons interact or ‘talk’ with each other, you could process the signal which is carried by just one single photon. This would allow us to process information in a completely new way and to build new devices like quantum computers.”

The next step in their research, according to Lukin and André, would be to trap light in all directions and to manipulate and interact trapped light pulses.