"We're going to be communicating with terabits of information in the next decade," says Mario Paniccia, an Intel fellow and director of the Photonics Technology Lab in Santa Clara, CA. A terabit of data is the capacity of roughly 35 DVDs. But today's fastest telecommunications networks use chips that zip data around at 10 to 40 gigabits per second, and most networks use expensive, clunky components that are assembled piecemeal and achieve lesser speeds. "The ability to have an integrated chip that can transmit and receive a terabit is a compelling solution, and we're still talking a chip the size of your fingernail," says ­Paniccia, holding in his palm three silicon chips that could prove to be the heart of that solution--thumbnail-size squares that reflect light like mirrors.

Photonic technology, which uses light to transmit data, is the key to networks with terabit-per-second speeds. But silicon, a mainstay of the electronics industry, has been largely useless for photonics because of its poor optical properties. Photonics researchers have had to rely on exotic semiconductors such as indium phosphide, which emit light easily but are expensive and hard to work with. But in 2004, ­Paniccia's group showed that silicon could be used to make a modulator that encodes data onto a light beam at one gigabit per second. (Telecom companies are beginning to use non-­silicon-based modulators that operate at 40 gigabits per second.) Then, in 2005, the Intel researchers bumped up the speed to 10 gigabits per second and built a surprisingly good all-­silicon laser (see "Intel's Breakthrough," July 2005).