Light-based microprocessor
The light-enabled microprocessor, a 3 x 6 millimetre chip, installed on a circuit boardUniversity of Colorado/Glenn Asakawa

Researchers have developed a processor that uses light for powering, instead of electricity like conventional chips. It is capable of transferring data at very high speed while consuming less energy.

Traditional processors powering laptops and supercomputers use electrical circuits to communicate with each other and transfer information. But researchers have now turned to photonics or, light-based processor technology. Besides, transferring data using light rather than electricity reduces the energy burden on the processor, as light can be sent across longer distances.

Jointly developed by the University of Colorado, the University of California, Berkeley, and the Massachusetts Institute of Technology (MIT), the microprocessor chip, measuring just 3mm by 6mm, transfers data quite fast. It has a bandwidth density of 300 gigabits per second per square millimetre, which is almost 10 to 50 times faster than electrical microprocessors.

"This is a milestone. It's the first processor that can use light to communicate with the external world. No other processor has photonic I/O in the chip," said Vladimir Stojanović, an associate professor of electrical engineering and computer sciences at the University of California, who led the research.

The use of the light-based chips is quite significant, starting from mobile devices to supercomputers to large data centres. Miloš Popović, an assistant professor in CU-Boulder's Department of Electrical, Computer, and Energy Engineering and a co-author of the study, said: "Light- based integrated circuits could lead to radical changes in computing and network chip architecture in applications ranging from smartphones to supercomputers to large data centres, something computer architects have already begun work on in anticipation of the arrival of this technology."

The chip that combines both optical circuitry and electronic circuitry, according to the researchers, can be integrated into the current manufacturing process with less difficulty.

"We figured out how to reuse the same materials and processing steps that comprise the electrical circuits to build high-performance optical devices in the same chip. This allows us to design complex electronic-photonic systems that can solve the communication bottleneck in computing," said Mark Wade, a PhD candidate at CU-Boulder.