Scientists work out how create 'trapped rainbow' by bringing light to a halt
Sydney, Nov 16: Researchers have worked out a theoretical means to create a ‘trapped’ rainbow by bringing light to a screeching halt inside a material that would separate the light into its constituent colours.
Boffins have been trying to bring light to a stop from its usual approximately 670 million mph (1.08 billion km/h) for years in hopes of revolutionizing how information is stored and sent.
During the current study, physicist Ortwin Hess of the University of Surrey and his team devised a theoretical means to stop light using what are known as metamaterials, or materials whose properties depend on their structure and not the composition of the material.
The property of these materials that makes them ideal for stopping light is their "negative refractive index" which is a measure of how much light slows down and reorients or bends as it passes through the medium.
Hess said that the property of metamaterials causes the light to bend somewhat back on itself and in such a way that "it gets slower and slower and eventually stops. "
The apparatus envisioned by the team would sandwich this metamaterial between two normal materials, with the metamaterial wider on one end and narrower on the other.
Hess said that these varying widths would cause the different wavelengths of light to stop at different points, so that "when every frequency component is trapped, they're spatially separated" in effect creating a rainbow of colours across the metamaterial, reports Live Science.
Hess's scheme remains in the theoretical realm for now, until metamaterials can be made small enough to manipulate the short wavelengths of visible light.
He said that if these light traps can be created, they could revolutionize information flow and storage.
Hess said that stopping light would also allow for storage of photons instead of electrons, which would enable more information to be stored on chips, because "optics have the inherent incredible bandwidth associated with it and so you could not only store one or two bits, but you could store... every single wavelength. "
The research has been published in the Nov. 15 issue of the journal Nature. (ANI)