Physicists conceive a ‘perfect absorber’
Fifty years after physicists invented the laser, ushering in everything from supermarket scanners to music CDs (SN: 5/8/10, p. 18), scientists have conceived its opposite — the “antilaser.”
Unlike its more popular cousin, the antilaser is unlikely to take over the world. Still, it could be useful one day, for instance in new types of optical switches for computers.
No one has yet reported building an antilaser, but a theoretical description of one appears in a paper published July 26 in Physical Review Letters.
“It’s kind of surprising that we’ve been using lasers for 50 years or so, and only now somebody noticed something pretty fundamental,” says Marin SoljaÄiÄ, a physicist at MIT who was not involved in the work.
Instead of amplifying light into coherent pulses, as a laser does, an antilaser absorbs light beams zapped into it. It can be “tuned” to work at specific w