Research shows promise for solid-state lighting.(News)(Research advances at Department of Energy's Sandia National Laboratories and at GE Global Research )

Separate research advances at the Department of Energy's Sandia National Laboratories and at GE Global Research are encouraging for two different approaches to making solid-state lights. Lights made from solid-state materials, including light-emitting diodes (LEDs), could potentially operate at much higher efficiency than incandescent or fluorescent lights, providing a new way to save energy.

Researchers at Sandia National Laboratories are building their lights from "quantum dots"--nanometer-sized dots of light-emitting material. The microscopic phosphors emit light without scattering it, so they are all efficient light source, and can be "tuned" to emit the right frequencies of light by changing their size and their surface chemistry. The trick, though, is encapsulating the dots without letting them clump together. Sandia solved that problem by chemically attaching the dots along the long-chain molecule that forms the encapsulating plastic. In the center of the plastic is an LED that emits near-ultraviolet light; the surrounding quantum dots absorb that light and ...