Data Packing Pulses For Optical Fiber
IN THE QUEST TO CRAM more information onto optical fibers, researchers are experimenting with exotic light waves called solitons. These waves keep their shape over long distances by interacting with the fiber in a way that generates higher frequencies in the back of the wave and lower ones in the front. Because solitons don't spread out, they can be packed more closely together and carry more information.
Yet even solitons diffuse as they lose energy, upsetting the perfect balance between different parts of the wave. So, scientists at Corning Inc. have developed a clever solution. They made a fiber that tapers just enough--10% over 25 miles--to keep the solitons in their original shape. In recent tests at the University of Rochester, graduate student Andrew Stentz showed that pulses as short as one-trillionth of a second travel the length of the fiber without any degradation. That could mean transmission systems 100 times as fast as those in use today.