Early research in metamaterials and transformation optics focussed on two main applications of negative index materials: cloaking and perfect imaging. In both cases, the ideal performance was severely degraded by losses in the metamaterials used to create the negative refractive index.
Now, researchers at Michigan Technological University have developed a novel technique to compensate for these losses in the optiucal regime, by injecting plasmons that allow a coherent optical amplification scheme. Importantly, it "...does not require a gain medium, interaction with phonons, or any nonlinear medium".
Perfect lenses could have a transformative effect on many fields, and especially the life sciences and semiconductor industry. The fabrication of integrated circuits using perfect lenses would benefit from the ability to resolve smaller details than currently possible for a given wavelength of light. For life sciences, perfect lenses could potentially allow the imaging of things like viruses and the interior structures in cells, including even DNA, using "standard" optical techniques, rather than the destructive imaging methods (such as electron microscopes) currently used for objects smaller than can be resolved optically.