Blazing-fast fiber-optic networks that carry vast amounts of data could become simpler and far less-expensive for companies to use, thanks to Bell Laboratories. Scientists there have developed a high-performance semiconductor laser, the world's first that operates across a wide spectrum of light.
Ultrawideband laser peaks at 1.3 watts.
Researchers built the laser using 650 alternating layers of two materials common to lasers, gallium indium arsenide and aluminum indium arsenide; each layer was just a few atoms thick. "The layer thickness determines the light that's emitted, not the chemistry of the material," says Claire Gmachl, a physicist at Bell Labs in Murray Hill, N.J., the research unit of Lucent Technologies Inc. The various layers form 36 different regions, or stacks, each able to generate light over a distinct optical wavelength. The different wavelengths emitted by the 36 regions are blended together to create a continuous wideband optical signal.
The laser is remarkably versatile, with a peak power output of 1.3 watts. "We're getting very good laser performance, but at many wavelengths," Gmachl says. The new laser can be used right now to detect the presence of trace gases to sense pollutants or combustibles or for breath analysis in the medical field. Once the wideband laser concept is applied to lasers operating in the ranges used in telecommunications networks, the wideband properties can be used to replace multiple lasers in an optical component, enabling the production of simpler, less-expensive optical networking equipment.