Scientists say they have slowed light to a dead stop, stored it and then let it go again.

Normally light is the fastest thing there is, travelling at about 299,000 kilometres a second (186,000 miles a second). But it is slowed slightly when it moves through some materials, such as glass.

The researchers have taken this effect to the extreme and say they have effectively made a beam of light stop after it entered a specially designed gas chamber.

The experiment has been hailed as a landmark that could pave the way for faster computers and totally secure communications.

All stop

The breakthrough has been achieved by two independent teams of researchers. One was led by Dr Lene Vestergaard Hau, of Harvard University, and the other by Dr Ronald Walsworth, of the Harvard-Smithsonian Center for Astrophysics, both in Cambridge, Massachusetts, US.



