Data Links Transmitting and Receiving at Unprecedented Rates

A new IBM transceiver, an integrated device which can transmit and receive record-breaking amounts of high-speed data in optical form, has been developed. The transmitting part of the device consists of 16 vertical cavity surface emitting lasers (VCSELs), lasers that emit light from the face of a semiconductor chip rather than from the cleaved edge of the chip. Each laser is capable of modulating a continuous laser beam at a rate in excess of 10 billion times per second (a record for individual devices in a transceiver), for a total data-sending rate of 160 Gigabits per second (Gb/s).

The 16-channel receiving part of the device operates at the same speed, for a simultaneous data-receiving rate of 160 Gb/s. The optical channels carrying the data can be either fibers or optical waveguides printed on a circuit board. Not only is the single-channel data rate unprecedented, but the power dissipation (15.6 mW/Gb/s) and the density (9.4 Gb/mm^2) are also unprecedented and key figures of merit. IBM is developing this transceiver as part of a Defense Advanced Research Projects Agency (DARPA)-sponsored chip-to-chip program designed to speed up communications between supercomputers.

Clint Schow of IBM will announce details of this work at next week’s Optical Fiber Conference (OFC) in Anaheim, California. (http://www.ofcnfoec.org/; Paper OThG4, “160-Gb/s, 16-Channel Full-Duplex, Single-Chip CMOS Optical Transceiver”)