In the quest to make computer processors smaller and faster, computing with light instead of relatively slow electrons has long been a tantalizing goal. One roadblock has been the inability to make lasers tiny enough so that several thousand of them could fit easily on a chip. In late August, two groups of researchers reported the construction of a new kind of nanometer-scale laser. Surface plasmon resonance nanolasers, or spasers, are the smallest lasers yet made, and their creators say the devices could pave the way toward ultrafast optical computing.
Spasers can "bridge the worlds of electronics and optics at truly molecular-length scales," says mechanical engineering professor Xiang Zhang, of the University of California, Berkeley, who led one of the groups with research associate Rupert Oulton.