The breakthrough could mean smaller supercomputers

Scientists at IBM have completed work that may make it possible to do away with the copper wires used to couple processing cores to each other.

The connector created by the team uses light to pass data between the computational cores that is faster and uses less power than copper wires.

The device is smaller than previously demonstrated connectors promising to shrink future computational clusters.

The IBM development, reported in the journal Optics Express, could replace the copper wires that connect cores with a device that converts electrical signals to pulses of light.

The device, called a silicon Mach-Zehnder electro-optic modulator, is many times smaller than previously produced convertors.

"What we have done is a significant step toward building a vastly smaller and more power-efficient way to connect those cores, in a way nobody has done before," said Dr Tze-chiang Chen, a spokesman for IBM's science and technology research division.

It could also boost the power of coupled computational cores because by using light, the speed at which data travels between the cores would be accelerated.

With light the researchers, led by Dr Will Green, can cut the amount of power needed to move data between processors and slash the amount of heat a large computational cluster produces.

The technology, which can transfer data up to a distance of a few centimetres, is about 100 times faster than wires and consumes one-tenth as much power, said Dr Green.

The lower power requirement should reduce operational costs for supercomputers.

Doing away with some of the cooling systems for computational clusters could shrink the systems further.

So far the team has only demonstrated the technology in a lab and it could be years before it makes its way into commercial chips.