Scientists at Lucent Technologies are said to have built the world’s first semiconductor laser that emits light over a wide spectrum of infrared wavelengths.
The laser, developed at the company’s Bell Labs, can be used to detect pollutants in the atmosphere, in medical diagnostic tools or in the future to produce semiconductor lasers for fibre optics.
‘An ultra-broadband semiconductor laser could be used to make an extremely sensitive and versatile detector that can detect minute traces of pollutants in the atmosphere,’ said physicist Claire Gmachl, whose research is published in the science journal Nature.
Semiconductor lasers have been narrowband devices that emit light of a single colour at a characteristic wavelength.
‘Previous lasers had a limited wavelength range. Part of the motivation of our work was to make a very wide, ultra-broadband laser,’ said Gmachl.
But she added that the wavelength could be much wider or narrower depending on the application.
‘We picked the range of six to eight micrometer for laser action as a good range for a convincing demonstration of the idea. In the future, one will be able to custom tailor the laser to the application, including fibre optics,’ Gmachl, the lead author of the Nature report, added.