Inexpensive computers, cell phones, and other systems that substitute flexible plastic for silicon chips may be one step closer to reality, thanks to new research published in the journal Nature Communications. The paper describes a proposal by NYU and University of Iowa researchers for overcoming a major obstacle to the development of such plastic devices—the large amount of energy required to read stored information. The above is a rendering that illustrates this process: an organic light emitting diode's light emission depends sensitively on the fringing fields from an electrically isolated magnetic film. The information stored in the magnetic material can thus be read optically.Image courtesy of New York UniversityInexpensive computers, cell phones, and other systems that substitute flexible plastic for silicon chips may be one step closer to reality, thanks to new research published in the journal Nature Communications.

The paper describes a proposal by New York University physicist Andrew Kent, Ferran Macià, a Department of Physics postdoctoral fellow, and their colleagues at the University of Iowa for overcoming a major obstacle to the development of such plastic devices—the large amount of energy required to read stored information.

Although it is relatively cheap and easy to encode information in light for fiber optic transmission, storing information is most efficiently done using magnetism, which ensures information will survive for years without any additional power.

“So a critical issue is how to convert information from one type to another,” says Michael Flatté, professor of physics and astronomy in the University of Iowa’s College of Liberal Arts and Sciences (CLAS) and director of the university’s Optical Science and Technology Center and one of the paper’s authors. “Although it does not cost a lot of energy to convert one to the other in ordinary, silicon-chip-based computers, the energy cost is very high for flexible, plastic computing devices that are hoped to be used for inexpensive ‘throwaway’ information processors.

“Here we show an efficient means of converting information encoded in magnetic storage to light in a flexible plastic device,” adds Flatté, who also serves as professor in the UI College of Engineering’s Department of Electrical and Computer Engineering.

What Kent, Macià, and their colleagues did was to successfully accomplish information transduction (or transfer and conversion) between a magnet and an organic light-emitting diode at room temperature and without electrical current flow between the magnet and the organic device.

“The magnetic fields from the magnetic storage device directly modify the light emission from the device,” adds Professor Markus Wohlgenannt, also of the Department of Physics and Astronomy and the Optical Science and Technology Center and one of the paper’s co-authors. “This could help solve problems of storage and communication for new types of inexpensive, low-power computers based on conducting plastics.”

Kent notes that while these studies were conducted on relatively large devices, miniaturized devices would operate on the same principles and enable new types of high capacity storage technologies.

The paper’s other co-authors were Fujian Wang and Nicolas J. Harmon of the UI Department of Physics and Astronomy and Optical Science and Technology Center.

The research was funded by the U.S. Army Research Office Multidisciplinary University Research Initiative grant (W911NF-08-1-0317).