College Park, MD (June 22, 2010) -- As cell phones and computers continue to shrink, many companies are seeking better ways to store hundreds of gigabytes of data in small, low-power devices.
A special type of liquid crystal, similar to those used in computer displays and televisions, offers a solution. Unlike CDs and DVDs, which store information only on their surface, lasers can encode data throughout a liquid crystal. Known as holographic storage, the technique makes it possible to pack much more information in a tiny space.
But attempts to use liquid crystals for data storage have had limited success. In order to reliably record and rewrite data, researchers must figure out a way to uniformly control the orientation of liquid crystal molecules. Currently, most liquid crystal technologies rely on physical or chemical manipulation, such as rubbing in one direction, to align molecules in a preferred direction.
In an important advance, scientists at the Tokyo Institute of Technology have created a stable, rewritable memory device that exploits a liquid crystal property called the "anchoring transition." The work is described in the latest issue of the Journal of Applied Physics, which is published by the American Institute of Physics (AIP).
Using either a laser beam or an electric field, the researchers can align rod-like liquid crystal molecules in a polymer. Their tests show that the liquid crystal created by the team can store data, be erased and used again.
"This is the first rewritable memory device utilizing anchoring transition," said Hideo Takezoe, who led the research. And because the device is bi-stable -- the liquid crystals retain their orientation in one of two directions -- it needs no power to keep images, adds Takezoe.
The article, "Heat- and electric-field-driven bistable devices using dye-doped nematic liquid crystals" by Hideo Takezoe et al will appear in the Journal of Applied Physics. See: http://jap.aip.org/
Journalists may request a free PDF of this article by contacting jbardi@aip.org.
ABOUT JOURNAL OF APPLIED PHYSICS
Journal of Applied Physics is the American Institute of Physics' (AIP) archival journal for significant new results in applied physics; content is published online daily, collected into two online and printed issues per month (24 issues per year). The journal publishes articles that emphasize understanding of the physics underlying modern technology, but distinguished from technology on the one side and pure physics on the other. See: http://jap.aip.org/
ABOUT AIP
The American Institute of Physics is a federation of 10 physical science societies representing more than 135,000 scientists, engineers, and educators and is one of the world's largest publishers of scientific information in the physical sciences. Offering partnership solutions for scientific societies and for similar organizations in science and engineering, AIP is a leader in the field of electronic publishing of scholarly journals. AIP publishes 12 journals (some of which are the most highly cited in their respective fields), two magazines, including its flagship publication Physics Today; and the AIP Conference Proceedings series. Its online publishing platform Scitation hosts nearly two million articles from more than 185 scholarly journals and other publications of 28 learned society publishers.
Journal
Journal of Applied Physics