Microprocessors Could Soon Use Light Rather than Electrical Signals


Microprocessors Could Soon Use Light Rather than Electrical Signals

25 February 2014
 
Researchers at the University of Colorado, Boulder, MIT and the University of California, Berkeley have developed novel photonic technology that could play a key role in the future of computing.
 
The team has created two devices, a modulator and a tunable filter, that bring photonic technology to a new level by showing that conventional chip-making processes can be deployed for developing low-power photonic devices.
 
The research, carried out as part of the Defense Advanced Research Projects Agency's (DARPA) Photonically Optimized Embedded Microprocessors (POEM) project, saw the creation of two energy-efficient devices built with the help of standard IBM advanced CMOS process. The devices help facilitate the communication link between a computer's processing unit and its memory. The modulator, in particular, turns electrical signals into optical signals, while the tunable filter can sort out light signals of certain frequencies and pick a signal carrying data from multiple frequencies. When combined with a photodetector, the filter converts optical signals into electrical signals.
 
According to researcher Mark Wade of the University of Colorado, Boulder, the study brings silicon photonics a step closer to some areas where electronics is the prevailing technology. It will enable the creation of complex electronic/photonic systems that require tight integration, he said.
 
Photonic devices can deliver ten times greater bandwith efficiency to chip-to-chip communication links and could be at least ten times more energy efficient than electronics. They can enable the transmission of more data in a smaller amount of space thanks to optical signals' capacity to use the same optical wire, unlike electrical signals, which require either multiple electronic wires or schemes for their transmission and more chip space and energy, Wade added.