Quantum Dots Could Light Up Your Life

Few inventions have changed the world like the light bulb. But time and technology have a way of replacing even the brightest ideas. In fact, light emitting diodes (LEDs) have been doing more of the world’s lighting work in recent years–not only in electronic devices, but in architectural lights, traffic lights, flashlights, and more.

LEDs have some serious advantages over incandescent bulbs. They’re sturdier, they produce twice as much light watt for watt, and they last 50 times as long. One problem: while LEDs are great for making colored light, they’re not so good at making the bright white light we like to live and work by. Until now, that is–thanks to an accidental discovery by Michael Bowers, graduate student at Vanderbilt University.

Bowers was cooking up a batch of quantum dots–tiny crystals a thousand times thinner than a human hair. And not just any quantum dots, but “magic-sized cadmium selenide nanocrystals,” which contain just 33 or 34 pairs of atoms. The dots were intended for a coworker’s research project, but when Bowers shined a laser on them he got a surprise all his own. They gave off “a beautiful white glow.”

Energized quantum dots normally give off colored light. As soon as Bowers saw the white light, he knew he was on to something. So he and another student mixed the quantum dots into polyurethane and coated a blue LED light bulb with quantum-dot goop. Result? An LED that gives off a warm, sunny light. Someday, instead of flipping on the lights, we might just energize the magic-sized dots.

via knowledgenews

Read more at vanderbilt