Post date: 13-Mar-2011 03:01:54
Yale University physicists have built an antilaser, a device capable of completely absorbing coherent light beams instead of scattering them as most other things do. If such a device proves practical, it might provide a way to build miniature silicon optical switches or lead to new types of photonic sensors.
The device works on the same principle as a laser but in reverse, and uses "time-reversal symmetry," a concept from electromagnetic theory. In essence, explains A. Douglas Stone, a professor of applied physics at Yale, "anything that could go forwards, the same process could go backwards."