07-10-2010, 01:37 PM
COMPUTERS THAT WORK WITH LIGHT INSTEAD OF ELECTRICITY.pptx (Size: 211.53 KB / Downloads: 99)
This article is presented by:
Jyotika Aggarwal
COMPUTERS THAT WORKS WITH LIGHT INSTEAD OF ELECTRICITY
INTRODUCTION
These days when computers had become an important part of one’s life, there is a good news for its users “Now computers can operate using light instead of electricity”.Today's fastest computers employ # miles of tiny copper wires. # each little ``brain'' or a miniature adding machine must exchange information with hundreds or thousands of partners on the same or connecting chips.``The weakest link in the overall capability of the computer is the ability to move information from chip to chip.Moving information around is the biggest limitation on the performance of computers, and it becomes a greater limitation as CPUs become faster.Computer scientists think that the solution may be photons, the tiny packets of energy that make up a beam of light.Photons can move data tens or hundreds of times faster than electrons on copper wires.
MIT researchers have demonstrated the first laser built from germanium # that can emit wavelengths of light useful for optical communications. # also the first germanium laser to operate at room temperature. Unlike the materials typically used in lasers, germanium is easy to incorporate into existing processes for manufacturing silicon chips. So the result could prove an important step toward computers that move data — and maybe even perform calculations — using light instead of electricity.
More fundamentally, the researchers have shown that, contrary to prior belief, a class of materials called indirect-band-gap semiconductors can yield practical lasers # As chips’ computational capacity increases, they need higher-bandwidth connections to send data to memory. # But conventional electrical connections will soon become impractical, because they’ll require too much power to transport data at ever higher rates. Transmitting data with lasers — could be much more power efficient, but it requires a cheap way to integrate optical and electronic components on silicon chips.