White coats at IBM today said they have built the world's teeniest optical switch, measuring 100 times smaller than the cross section of a human hair.

Big Blue said its new nanophotonic switch device brings the company another step closer to creating computer chips that use light pulses instead of electrical signals on copper wires.

Once electrical signals are converted into pulses of lights, the tiny device ensures that optical messages are efficiently directed from one processing core to another.

IBM contends in a paper published in the journal Nature Photonics that the old wire way will become yesterday's news when on-chip optical interconnects are — cough — finally brought to light.

Specifically, the promise of optics will become more and more appealing as chip makers continue to increase processing cores at roughly the same speed that shaving supply companies add superfluous blades to their razors. Copper wires, they argue, could simply use up too much power and be incapable of transmitting the enormous amount of information between massively multi-core processors.

Switches represented by black boxes

The researchers say each individual wavelength in an optical switch can transfer data at up to 40Gb/s. And because the switch is able to route different wavelength "colors" of light simultaneously, IBM claims aggregate bandwidth can exceed 1Tb/s. They envision using light will multiply the speed information is sent between cores by as much as 100 times, while using 10 times less energy.

The company said its tiny switch is ideally suited for on-chip applications because of the sheer lack of scale. Big Blue estimates that as many as 2,000 of the devices could fit side-by-side in an area of one square millimeter. (Which by the way means that if each device was mounted by an angel, a full 4,000 could dance on the head of a pin. Who says computer chips and ontology don't mix?)

Optical switch (bright red, actual size)

IBM scientists assert that their optical switch is also rugged enough for the hardcore, heated world of semiconductors. The optical switch is capable of operating in an environment with changing "hot-spots" that move around depending on the processing function.

The full report is titled "high-throughput silicon nanophotonic wavelength-insensitive switch for on-chip optical networks," by Yurii Vlasov, William Green and Fengnian Xia of IBM's T.J. Watson Research Center in New York state. Find the August issue of Nature Photonics right next to Cat Fancy and Root Vegetables Today in fine newsstands everywhere. ®