Now, metamaterial brakes to speed up the net

London, Aug 15 : Scientists have found the key to speed up the Internet -metamaterial brakes.

"Metamaterials" will make it possible for the scientists to create invisibility cloaks to slow down the information travelling in different channels through fibre-optic cables. It's not the transportation of information that limits the speed of intenet, but it gets slowed down at the time of routing the information to its various destinations.

This problem could be solved by metamaterials, that can replace the bulky and slow electronics that do the routing, paving the way for lightning fast speeds. Usually, high-speed telecommunications is facilitated by routes including fibre-optic cables that span vast distances, carrying different streams of information in different channels, each with its own frequency of light.

At the time when the data is about to end its journey, these frequencies need to be separated and sent to their destinations. This is made possible by bulky equipment that spreads the closely spaced frequencies in the pulses into different detectors. This slowing down of light poses the biggest problem for telecoms. The light must then be converted into electrical signals, which are stored, routed, and turned back into optical signals with lasers.

This conversion, not only adds significant cost and complexity, but also slows down the data transmission.

"It limits the speed of the whole process to the speed of your electronics," the New Scientist quoted Dr Chris Stevens from the department of engineering sciences at the University of Oxford, as saying.

He added: "The light and the fibres can quite cheerfully sustain a couple of terahertz, but your electronics can't do more than a few gigahertz."

That's where the metamaterials could be put to use. If the light signals could be slowed sufficiently during the switching process, there would be no need for the electrical conversion step.

It is the design that holds the key to the optical properties of metamaterials, which is why they are touted for use in cloaking, and thus they can be engineered to deliberately slow light down.

The effect could be used to store light signals, with different delays for different frequencies, in a so-called "all optical network".

"The ability to slow the light could be a tremendous force for telecoms that is sure to enhance speed and efficiency," said Professor Xiang Zhang, the University of California researcher who demonstrated cloaking earlier this week.

The metamaterials could be engineered to accomplish the frequency spreading step as well, working much like a prism that splits white light into a rainbow.

"With these materials, you could imagine something more like a single chip with the metamaterial handling the routing-all the capability of one of these big filtering systems, but the size of your fingernail," said Stevens.

ANI