MIT boffins predict interplanetary broadband

A new detector will allow the real-time collection of large amounts of data from space

Boffins at MIT labs this week unveiled a tiny light detector that may allow for super-fast broadband communications over interplanetary distances.

At present, even still images from equipment on other planets are difficult to retrieve, but the new detector improves the efficiency for single photos to 57 per cent at a wavelength of 1,550 nanometres.

This is the same wavelength used by fibre optics to carry broadband to offices and homes today, and is nearly three times the current detector efficiency of 20 per cent.

"It can take hours with the existing wireless radio frequency technology to get useful scientific information back from Mars to Earth. But an optical link can do that thousands of times faster," said Karl Berggren, assistant professor in the Department of Electrical Engineering and Computer Science at MIT.

The detector will allow the real-time collection of large amounts of data from space, and may ultimately permit the transmission of colour video between astronauts or equipment in outer space and scientists on Earth.

The detector, which uses nanowires and superconductor technology, can sense extremely low light or laser signals in the infrared part of the optical spectrum down to a single photon, the smallest and most basic unit of light. This has not been possible using conventional optical systems.

Because of the vast distances between planets, current optical systems would require a large laser and a lot of power to send data at a high rate. And this would have to be done on spacecraft, which are typically starved of power.

So there is a need for devices like the new detector that can operate quickly and, because they are more sensitive, receive signals from smaller lasers that do not use much power, Berggren explained.

The detector also could be applied to quantum cryptography and biomedical imaging, but the most immediate application is probably interplanetary communication.