IBM develops ultra-fast device which uses light for communication between computer chips
As of now computer chips use electric current to communicate with each other. But fast-forward couple of years and computer chips may well use light for internal communications. Reportedly, IBM scientists have developed an ultra-fast device which uses light for communication between computer chips. The device, called a nanophotonic avalanche photodetector, is the fastest of its kind and could enable breakthroughs in energy-efficient computing that can have significant implications for the future of electronics.
The IBM device explores the “avalanche effect” in Germanium, a material currently used in production of microprocessor chips. Analogous to a snow avalanche on a steep mountain slope, an incoming light pulse initially frees just a few charge carriers which in turn free others until the original signal is amplified many times. Conventional avalanche photodetectors are not able to detect fast optical signals because the avalanche builds slowly.
The avalanche photodetector demonstrated by IBM is the world’s fastest device of its kind. It can receive optical information signals at 40Gbps (billion bits per second) and simultaneously multiply them tenfold. Moreover, the device operates with just a 1.5V voltage supply, 20 times smaller than previous demonstrations. Thus many of these tiny communication devices could potentially be powered by just a small AA-size battery, while traditional avalanche photodetectors require 20-30V power supplies.
So where do we go from here? Well, many such devices can be built with silicon transistors for high-bandwidth on-chip optical communications.
