The smallest, most efficient laser yet, a nanoscale device that consumes just 1 microwatt of power, could one day be a component of faster computers.
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Toshihiko Baba of Yokohama National University in Japan and his colleagues constructed the tiny laser out of a photonic crystal—a material with internal microstructure that controls the behavior of selected wavelengths of light. In nature, photonic crystals are responsible for the iridescent surfaces of some butterfly wings.