Seeing through physics

Childhood fantasies of seeing through brick walls and closed doors could be a step closer to reality following work by researchers from

and the

,

.

They have developed a technique that, under laboratory conditions, makes solid objects appear transparent. The effect exploits the way electrons move in matter.

Overturning Einstein

Normally, when light is shone on to a material, the light's energy is absorbed by its electrons. However, using a new material created from nanoscale crystals, an 'X-ray effect' has been achieved by shining a laser on to the structure to 'control' the 'wave-like' character of the electrons in such a way that they interfere with one another. The material then ceases to absorb light, becoming transparent in the process.

The work is based on a breakthrough that contradicts Einstein's theory that for a laser to work, the light-amplifying material it contains, usually a crystal or glass, must be brought to a state known as 'population inversion'.