LEDs have changed the way the world uses lighting, and a new design, using tungsten diselenide, may revolutionize the industry. This new design is thinner than a human hair, yet is incredibly resilient to wear. Like all LEDs, this new model is extremely energy-efficient.
Light-emitting diodes (LEDs) are constructed from semiconductors. As electrons pass through the material, light is produced. Appliances and electronics including televisions, computer monitors and smartphones all rely on LED lights to make them work. These personal and home devices are becoming smaller, driving a demand for smaller, more efficient semiconductors.
The new design is designed from "two-dimensional" flexible semiconductors. These can be stacked on top of each other and used for a wide variety of applications, in a multitude of configurations. The LED's in current electronic systems are 10 to 20 times thicker than the new design.
Although the new lights are not truly two dimensional, the semiconductors are just three atoms thick - that is the thinnest possible configuration for such a device, given current knowledge.
"These are 10,000 times smaller than the thickness of a human hair, yet the light they emit can be seen by standard measurement equipment," Jason Ross of the University of Washington said. He led the research with Xiaodong Xu, an assistant professor at the school.
Building computer chips based on these thin semiconductors could reduce heat - and energy costs - over current processor technology.
"Our work makes it possible to make highly integrated and energy-efficient devices in areas such as lighting, optical communication and nano lasers," Xu said.
This high-tech gadget gets its start from a material we all used in kindergarten - regular adhesive tape. This simple tool is used to peel away thin layers of tungsten diselenide from a sample. A similar process, producing graphene from graphite, won the Nobel Prize in Physics for 2010.
In the 1970's, early LED watches cost thousands of dollars. Recently, electronics manufacturer LG announced a new organic light emitting dioode (OLED) television just one-sixth of an inch thick. They took out an ad for the new set on the binding of a thin magazine. The new LED will ultimately allow electronics to become even thinner than that.
Researchers are currently investigating various stacking techniques for the new semi-conductors. Such devices seem to have an odd reaction to polarized light, unlike any other material. University of Washington investigators have yet to publicly detail information on that phenomenon.
Investigation into the ultra-thin LED's was sponsored, in part, by the U.S. Department of Energy.
