MIT professors attack last-million-mile problem

Network World - If you think your wireless is slow, imagine what it's like to be a scientist waiting for data being beamed back from Mars via wireless radio frequency technology.

"It can take hours,'' said Karl Berggren, an assistant professor in MIT's Department of Electrical Engineering and Computer Science.

But Berggren and his colleagues have developed a tiny light detector that may lead to high-speed optical transmissions over interplanetary distances. The upshot could be real-time collection of large amounts of data from space, and ultimately color video transmissions between astronauts in outer space and scientists on Earth.

Single-photon detectors aren't new, but they have not been both speedy and efficient at detecting light. However, Berggren added a "photon trap'' and antireflection coating to boost the efficiency of the detectors.

The photon trap consists of a nanowire detector, a carefully measured gap of glass and a mirror. The nanowire is tightly coiled and then cooled to just above absolute zero. At that temperature, it becomes a superconductor and can detect the absorbed photons.

Berggren and his colleagues, whose work is partially funded by the U.S. Air Force, published their discovery in the Jan. 23 issue of Optics Express.