NBF carries the story.

No matter how powerful a conventional lens, it cannot focus light down to more than about half its wavelength, the “diffraction limit”. This limits the amount of data that can be stored on a CD, and the size of features on computer chips.

Researchers have devised ways to beat the diffraction limit before, using bizarre “metamaterials” that are hard to make, and which are also the basis of prototype “invisibility cloaks”.

http://technology.newscientist.com/article/dn13771-simple-superlens-sharpens-focusing-power.html