London, November 21 : US researchers might have moved one step closer to creating the next generation of electronic devices with increasingly smaller components, with the discovery that the electronic behaviour at the surface of a class of minerals called manganites is considerably different from that found in its bulk.
John Hill, a physicist with the Department of Energy's Brookhaven National Laboratory, says that understanding the characteristics of a material's surface is important to predict how such materials behave, and how electrons will travel across an interface.
Manganites show a huge change in electrical resistance when a magnetic field is applied.
Hill believes that this "colossal magnetoresistance effect" may be the key to developing advanced magnetic memory devices, magnetic field sensors or transistors.
During the course of the study, the researchers used x-ray scattering at Brookhaven's National Synchrotron Light Source and Argonne's Advanced Photon Source to study the orbital order of the material at its surface and in its bulk.
"When you cool down the bulk material to a particular temperature, all the orbitals arrange themselves in a very particular pattern. The question is, does the same thing happen at the surface? And if not, how is it different?" Nature Materials quoted Hill as saying.
The study revealed that at the surface of the mineral, the orbital order was more disordered than in its bulk. While the manganite's crystal surface was atomically smooth, its orbital surface was rough.
According to the researchers, such characteristics of the mineral may affect the way electrons are transferred across its surface.
They also say that the new findings provide fundamental information for future research and development.
The researchers are now planning to look for the surface orbital "roughness" in other materials, and test its effect on magnetism.
The study was funded by the Office of Basic Energy Sciences within in the U.S. Department of Energy's Office of Science. (ANI)
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