The Princeton team, which also included researchers from Oregon State University in Corvallis and the Murray Hill, N.J.–based telecommunications firm Alcatel-Lucent, is hoping that improved lenses could lead to sensor systems that can measure low concentrations of chemicals in the air. "Chemical trace gases that are vapors under normal conditions have characteristic absorption features," Gmachl says. Sensors that are able to identify the chemical fingerprints could be used to warn people when harmful chemicals have been released into the air, either on purpose or inadvertently. Medical professionals might also be able to use such a sensor to check a patient's breath for traces of chemicals that indicate liver disease or internal inflammation.
Beyond the development of new sensors, semiconductor metamaterials such as the one Hoffman and his team created will also improve light amplification used in lasers. "Having a new material with improved optical properties just enhances the toolbox of the things we can work with," Gmachl says, adding, however, that most of this technology today is only in the prototype phase "There is still much work to be done. You won't find these in commercial deployments yet."