CHICAGO, July 3 (Xinhua) -- An international team including researchers at the University of Michigan (UM) has devised a way to make optoelectronic materials from cheaper, more abundant elements.

According to a news release posted on UM's website on Tuesday, the researchers used a technique called molecular beam epitaxy (MBE) to produce the desired compounds under the correct conditions to make films with a carefully controlled degree of atomic ordering.

MBE lays down each atomic layer of the compound in a systematic fashion, so the researchers could study the thin layer, or film, structure as they were growing it.

The new compound of zinc, tin and nitrogen can harvest both solar energy and light, so it would work in thin-film solar panels as well as in LED light bulbs, cell phone screens and television displays.

Using magnesium instead of zinc further extends the reach of the materials into blue and ultraviolet light. Both compounds are also "tuneable," that is when the researchers grow crystals of either compound, the elements can be ordered in such a way that the material is sensitive to specific wavelengths of light.

This tunability is desired because it allows researchers to tweak the material to respond to the widest range of wavelengths of light. This is especially important for light-emitting diodes so that device designers can select the color of light produced.

"When you're lighting a home or an office, you want to be able to adjust the warmth of the light, oftentimes mimicking natural sunlight," said physicist Roy Clarke, who leads the UM effort. "These new compounds would allow us to do that."

Currently, only specific kinds of compounds, a combination of two or more elements, can be used to make electronic devices that efficiently emit light or gather electricity. "We're in danger of running out of some of those elements because they're not easy to recycle and they're in limited supply," said Clarke. "It's not viable for technology to rely on something that's likely to run out on a scale of 10 to 20 years."

The research has been published in Physical Review Letters. Enditem

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