IBM builds optical switch for multicore chips

Computerworld - IBM today announced that its scientists have built a switch that can control the flow of information on a chip using pulses of light instead of electrons.

The new nanotech switch, which is 100 times smaller than a human hair, is designed to enable researchers to build chips that will have greater performance but use less energy, IBM said on Monday.

"This new development is a critical addition in the quest to build an on-chip optical network," said Yurii Vlasov, manager of silicon nanophotonics at IBM, in a statement. "In view of all the progress that this field has seen for the last few years, it looks that our vision for on-chip optical networks is becoming more and more realistic."

Today's news comes just months after IBM disclosed that it is working on a project to shrink supercomputers down to the size of a laptop by replacing the electrical wiring that now connects multiple cores inside a microprocessor with pulses of light. The company said the laptop supercomputers should be ready by 2020. Calling it a "breakthrough" in chip design, IBM said using optical communication between the cores would dramatically cut a processor's energy needs and the heat it emits. The new chips would require the energy needed to power a light bulb, while today's supercomputers need enough energy to power hundreds of homes, the company noted.

Today's announcement focuses on transmitting information using pulses of light traveling through silicon instead of using electrical signals on copper wires.

In a paper published in the journal Nature Photonics, IBM explained that once electrical signals are converted into pulses of light, the new switching device basically directs traffic within the network, enabling the now-optical messages to move from one processor core to any of the other cores on the chip.

IBM also noted that as many as 2,000 switches would fit side-by-side in one square millimeter.