"This is the first time anyone has done really fundamental, hands-on quantum mechanics with an organic LED," Lupton said in a news release announcing the study. "This is tough stuff."

Lupton and Boehme conducted the study with postdoctoral researcher Dane McCamey and four University of Utah physics doctoral students: Heather Seipel, Seo-Young Paik, Manfred Walter and Nick Borys.

The findings further research published in 2004 in which another team of U. physicists reported building the first organic "spin valve" to control electrical current. In the new study, the researchers showed that information can be carried by spins in an organic polymer, and that a spin transistor is possible because "we can convert the spin information into a current, and manipulate it and change it," Lupton said.

"Even the smallest transistor today consists of hundreds of thousands of atoms," says Boehme. "The ultimate goal of miniaturization is to implement electronics on the scale of atoms and electrons."

The new research reveals an old shadow on deciphering the nature of light — light bulbs put out more heat than light. (The lamps over the row of french fries at the fast food place aren't there to brighten their appearance but to keep them hot.)

LEDs these days can convert 47 percent to 64 percent of incoming electricity into white light rather than waste heat. But efforts to replace incandescent and even compact fluorescent light bulbs with LEDs have been hindered by costs exceeding $100 per LED bulb.

"Doping" or adding other chemicals to organic semiconductors to make them more efficient might lead to organic LED efficiencies above 25 percent, but new research dims that hope.

Organic LEDs' greatest promise is not lighting but in revamping liquid crystal display (LCD) technology in modern televisions and computer screens. Boehme believes organic LEDs will be much cheaper, can be made on flexible materials, have a wider viewing angle and color range and will be more energy efficient than LCDs.

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