A Step Toward Optical Routing
Contemporary routing solutions mainly involve electricity, which is inefficient as the process involves the conversion of bursts of light into electrons and back again. The alternative, optical routing, has been a challenge because pulses of light are difficult to control. That may soon change as scientists at Cornell University are working on a small compact device, on the order of micrometers, that uses optically controlled containers that open and close to store and release light. The ability to store pulses of light opens the door to the possibility of being able to control the order of information flow and timing, which are two very important variables in routing communications.
"The Cornell device includes two parallel silicon tracks… Between these two tracks two silicon rings… Light of a certain color passes along the silicon track, takes a detour through one of the rings, and then rejoins the silicon track and continues on its way. However, if the rings are retuned to the same frequency the moment after a light pulse enters a ring, the light pulse will circulate between the rings in a continuous loop rather than rejoin the silicon track and escape. Tuning the rings to different frequencies again, such as by shining another pulse on one of the rings, allows the light to escape this circuit and continue on to its destination."
The leading researcher, professor Michal Lipson of computer and electrical engineering, and colleagues have declared that the project is still in its early stages and commercial prospects are still a bit far off. At the moment, the rings in their device only store a small part of burst of light, which means that any encrypted information will be lost. “The new approach is an important step forward because it makes it possible to store light in ambient conditions and in a very small device. Once you’ve done that, then it becomes interesting to industry,” asserts Marin Soljacic, a physics professor at MIT.