Faster, Cheaper Fiber Optic Cables Possible with New Technique Developed at Yale

By changing the optical properties of the semiconductor material gallium arsenide (GaAs), a Yale researcher has found a faster and cheaper way to create crystals for optical emitters, which have potential uses in fiber optic cables to carry television pictures and sound.

Fiber optics transmit a specific kind of infrared light that is invisible to the naked eye. This light is very expensive to produce using current materials. To address the cost, Janet Pan, assistant professor of engineering at Yale, used GaAs, as a new source of the infrared light. This semiconducting material is reliable and inexpensive and is currently used in cell phones and lasers.

Because GaAs is not naturally compatible with low loss (higher quality) fiber optics, Pan redesigned the material to make a new light source.

“I was able to make GaAs compatible with long-distance fiber-optics, something not currently done with this material,” said Pan who recently published results of her study in Nature Materials. “This could lead to inexpensive high speed fiber-optic communications over long distances at 1.5 micrometers, with an increase in speed of 200 times.”

Pan is currently testing ways to make the light source brighter so it can send stronger signals.

“The next steps are to increase the efficiency and to reduce the operating currents,” said Pan. “Practical devices from this technology could be available in the next three to five years. These devices could potentially transmit information inexpensively at a trillion times per second.”