IBM researchers recently developed a chip which can transmit and slow down the speed of light, thus bearing some features of photonic memory in the future. The research report was carried on Nature magazine published on November 3.
Optical transmission is the most used in world communication networks due to its much higher efficiency than electronic transmission. But information storage is difficult and optical signals must be converted to electronic ones before they can be stored.
However, scientists have developed two technologies to handle photons. In 1999, Harvard physicists made photons pass through cold atoms to slow down their speed to that of a bicycle. The "slow light" technology can help buffer optical data but it needs large amounts of instruments.
Other scientists invented a small channel named "waveguide" to make photons pass through opaque substances such as silicon, thus forming material similar to electronic chip.
Researchers from IBM's T.J. Watson Research Center combined the two technologies to develop a chip with photonic waveguide and reduce light speed to 1/300 of its normal level by heating the waveguide. A basic idea in developing the chip is to slow down some data while waiting other data to catch up, so as to realize simultaneous processing.
