PERSUADING light to dawdle may be much easier than anyone thought.
Physicists recently managed to slow a pulse of light to just 17 metres per
second as it passed through a soup of extremely cold atoms
(This Week, 20 February, p 10).
But chilling atoms to just above absolute zero is expensive and
few labs can afford to do so.
Now Michael Kash of Texas A&M University in College Station and his
colleagues have achieved the same feat using a cloud of rubidium gas heated to
87 °C. In their experiment the light pulse travelled at around 90 metres per
second along a chamber filled with the gas—about a million times more
slowly than usual (Physical Review Letters, vol 82, p 5229). The team
hopes the effect may lead to new optical technologies.
