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In a decade, some scientists expect there to be no buzzing from loud fans in laptops and say MP3 players will ideally run at least 100 times faster because electronic chips will be dominated by silicon optical amplifiers, an advancement based on the discoveries in engineering announced two weeks ago.

A group of researchers at the UCLA Henry Samueli School of Engineering and Applied Science announced on June 28 a breakthrough in the development of silicon photonics. Scientists hope that by using silicon in short-distance communication, information can be transferred with great speed and no energy cost.

After scientists in the UCLA engineering department demonstrated the first use of the silicon laser in 2004 and Intel contributed by allowing the use of continuous light, a team headed by electrical engineering Professor Bahram Jalali started a project to research silicon chips.

With silicon becoming increasingly important in electronics, the goal of the project was to combine silicon and optics, or light, for chip-to-chip communication.

“Silicon is the wonder material of modern times,” Jalali said.

By replacing the copper wires that are currently being used to connect chips with silicon, optics can address the common problem of speed because light is being used, said Kevin Tsia, a graduate student in the School of Engineering who is participating in the research.

“We’re always trying to shrink the size and increase the speed of electronic devices,” Tsia said. “But the bottom line is that copper wires cannot accommodate such speed. Optics can.”

The main problem with using silicon, however, is that it becomes opaque at high optical intensities due to the process of light absorption called two-photon absorption, causing additional loss of energy, Jalali said.

Postdoctorate fellow Sasan Fathpour and Tsia found a way to overcome that problem through silicon’s light-harvesting characteristic known as the Raman effect.

“We had to think outside of the box to see that the photovoltaic property could be applied in a way similar to that of solar cells using sunlight to harvest energy,” Fathpour said.

Not only would no energy be required, compared to the 1 watt of input energy that would be needed to amplify light without using the Raman effect, but a few milliwatts of power can even be generated, Jalali said.

“This development is a major stepping stone because power dissipation is the No. 1 problem right now,” Jalali said.

The three greatest areas of direct impact will be in chip communication, optical sensors and high-power lasers used for defense, Jalali said.

Now that the use of silicon in photonics to generate energy has been discovered, the next step will be to reduce the size of the chips that use silicon from centimeters to microns so they can fit in devices, Jalali said. Currently, silicon chips can be made, but are still too big to use.

“We’ve made significant progress but it won’t be another three to five years until silicon photonics will be available in industry,” Jalali said.