In an advance that could inexpensively speed up corporate data centers and eventually personal computers, researchers used everyday silicon to build a device that converts data into light beams.
Light-based communications has until now largely been the realm of large telecom companies and long-haul fiber-optic networks because of the expense of the exotic materials required to harness photons, the basic building block of light.
Now, researchers at Intel Corp. say their results with silicon promise to reduce the cost of photonics by introducing a well-known substance that’s more readily available.
A billion bits per second
In the study, published in Thursday’s journal Nature, the Intel researchers reported encoding 1 billion bits of data per second, 50 times faster than previous silicon experiments. They also said they could achieve rates of up to 10 billion bits per second within months.
“This is a significant step toward building optical devices that move data around inside a computer at the speed of light,” said Pat Gelsinger, Intel’s chief technology officer.
Intel believes the finding could have profound implications for the links between servers in corporate data centers. Eventually, the technology could find its way into personal computers and even consumer electronics.
“It is the kind of breakthrough that ripples across an industry over time, enabling other new devices and applications,” Gelsinger said. “It could help make the Internet run faster, build much faster high-performance computers and enable high bandwidth applications like ultra-high-definition displays or vision recognition systems.”
Unlike electrons that flow through copper connections common today, the photons in light are not susceptible to data-slowing interference and can travel farther.
The Intel researchers built a device called a modulator, which switches light into patterns that translate into the ones and zeros of the digital world.
A light beam was split into two as it passed through the silicon, which has tiny transistorlike devices that alter light. When the beams are recombined and exit the silicon, the light goes on and off at a frequency of 1 gigahertz, or a billion times a second.
Infrared light is used because it can pass through silicon.
“Just as Superman’s X-ray vision allows him to see through walls, if you had infrared vision, you could see through silicon,” said Mario Paniccia, a study author and director of Intel’s silicon photonics research. “This makes it possible to route light in silicon, and it is the same wavelength typically used for optical communications.”
Future for photonics
The researchers expect to be able to increase the frequency to 10 gigahertz, making the technology commercially viable, said Victor Krutul, senior manager of Intel’s silicon photonics technology strategy.
“What we’re doing here with this announcement is we’ve figured out how to do it. Punching through the (previous record of 20 megahertz) and finding the new processes to do it were the real breakthroughs,” he said. “Getting it to 10 gigahertz is just engineering.”
Graham T. Reed, a professor of optoelectronics at the University of Surrey’s Advanced Technology Institute, agreed that silicon opens up a bright future for photonics.
“This implies that the economies of scale that we have seen for the electronics industry could one day apply to the photonics industry,” Reed said in a commentary that accompanied the research paper.