Intel: cheap optical computing is the future
25th Jul 2007 | 23:00
Findings mean high bandwidth, low cost for optical computers
Intel researchers have created a new type of laser that can encode data at 40 million bits per second (40Gbps). It's a crucial development in Intel's ongoing research into optical computing.
Optical computers will use light instead of electricity to process data (that's photons rather than electrons), thereby improving the efficiency and speed of processing. All optical computing developments are still in the early stages.
Ansheng Liu, writing on Intel's Research Blog , says that a photonic integrated circuit (PIC) could pave the way to cheap optical processing in the future. "PICs on silicon platforms have attracted particular interest because of silicon's low cost and high volume manufacturability," he says.
"As you may know, a PIC could provide a cost-effective solution for optical communication and future optical interconnects in computing industry," says Liu. "PICs on silicon platforms have attracted particular interest because of silicon's low cost and high volume manufacturability."
High-speed silicon optical modulator
The ability to transmit such an amount of data optically isn't new, but the components previously tried were expensive. "One of the key components needed for silicon PICs is the high-speed silicon optical modulator, which is used to encode data on optical beam," says Liu.
"Today's commercially available optical modulators at 10 Gbps are based on more exotic electro-optic materials such as lithium niobate and III-V compound semiconductors. Using a PIC could dramatically speed up the development of optical computing."
Liu says replicating 40 Gbps speeds in silicon PICs has been difficult because "crystalline silicon does not exhibit the linear electro-optic (Pockels) effect used to modulate light in these materials. Engineers are forced to rely on the free-carrier plasma dispersion effect, in which silicon's refractive index is changed when the density of free carriers (electrons/holes) is varied, to modulate light in silicon."