IBM closer to chips with frickin' laser beams
Debuts teeny-tiny optical detector
IBM scientists say they're another step closer to creating computer chips circuits that efficiently use frickin' laser beams rather than copper wires to communicate.
On Wednesday, Big Blue's light-wrangling boffins  unveiled what's called an avalanche photodetector capable of receiving optical information pulses at 40Gbps. The device also operates with just a 1.5V voltage power supply, rather than the 20V to 30V power supplies required by existing devices.
Furthermore, the device is made of silicon and germanium. Both materials are already widely used in the production of traditional microprocessors and fabricated using standard processes for chip making.
The key to such a device is the namesake "avalanche effect," which occurs in the germanium. Incoming pulses of light free just a few electrons as well as electron holes (basically, the lack of an electron in the position of where one could exist). Those electrons and holes in turn free other electrons and holes, and so on, until the information encoded on the light pulse is amplified ten-fold. This allows for weak light pulses trekking across a silicon chip.
IBM claims photodetectors made by rival science squads like Intel  aren't able to detect optical signals as fast because the avalanche builds too slowly and because the process using traditional germanium photodetectors degrade the signals. It claims these hurdles were cleared using unspecified "nanoscale effects".
Unfortunately, your home PC won't chip the light fantastic any time soon. Big Blue said that what it's showing today is just one of the many components necessary to put nanophotonic devices on a general use microprocessor chip. Actual integration won't happen for five to ten years, IBM estimates. ®