X-ray Specs No Longer Required

A new optical effect has been created in a London laboratory that means solid objects such as walls could one day be rendered transparent, researchers report today in the journal Nature Materials.

Scientists from Imperial College London and the University of Neuchatel, Switzerland, have pioneered the technique which could be used to see through rubble at earthquake sites, or look at parts of the body obscured by bone.

The effect is based on the development of a new material that exploits the way atoms in matter move, to make them interact with a laser beam in an entirely new way.

The work is based on a breakthrough which contradicts Einstein's theory that in order for a laser to work, the light-amplifying material it contains, commonly a crystal or glass, must be brought to a state known as 'population inversion'. This refers to the condition of the atoms within the material, which must be excited with enough energy to make them emit rather than absorb light.

Quantum physicists, however, have long predicted that by interfering with the wave-patterns of atoms, light could be amplified without population inversion. This has previously been demonstrated in the atoms of gases but has not before been shown in solids.

In order to make this breakthrough, the team created specially patterned crystals only a few billionths of a metre in length that behaved like 'artificial atoms'. When light was shone into the crystals, it became entangled with the crystals at a molecular level rather than being absorbed, causing the material to become transparent.



Source: Imperial College London

Posted by: Scott    Source