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Graphene, the hottest new material inelectronics, is remarkably simple: a flat sheet of pure carbonrings�just one atom thick�that resembles chicken wire. But thisunassuming structure has caught the attention of researchers atlaboratories in the United Kingdom, Texas, and Georgia and even at IBM.They are studying graphene for a wide range of applications, fromcomputer chips to communication devices to touch screens. It might evenput a fresh spark into the electrical grid.Consisting of asingle layer of graphite, graphene is an allotrope of carbon that hasbeen studied for decades. It did not seem technologically important,however, until scientists began looking at potential replacements forsilicon in electronics. In 2004 physicists at the University ofManchester in England demonstrated a simple way to producegraphene�peeling off layers of graphite, a method known as mechanicalexfoliation�spurring an explosion of research.Graphene hasseveral very appealing traits. Electrons meet much less resistance fromgraphene than they do from silicon, traveling through it more than 100times as easily. And because graphene is essentially a two-dimensionalmaterial, building smaller devices with it and controlling the flow ofelectricity within them are easier than with three-dimensionalalternatives like silicon transistors.In a blown-up image froma scanning tunneling microscope, it looks just like an endless sheet ofchicken wire: a simple flat sheet made up of a lattice of hexagons. Butthis nanoscopic material called graphene, first generally acknowledgedto exist just five years ago, turns out to have a variety of unique,and potentially very useful, characteristics -- ones severalresearchers are actively trying to better understand and turn intoreal-world applications.Graphene, a form of the element carbonthat is just a single atom thick, had been identified as a theoreticalpossibility as early as 1947. Even as Institute Professor MildredDresselhaus, her physicist husband Gene, and others were working in the1960s with multiple layers of graphene, many scientists were sayingthat such an ultra-thin sheet of matter could never be found or evenmade. It was very controversial; there were many people who wereskeptical.Now that it has been found, with widely publicizedresults published in 2004 by researchers. They are focusing on how toharness its properties, and trying to find ways to produce it insufficient quantity for extensive research and eventually forcommercial applications.Its unique electrical characteristicscould make graphene the successor to silicon in a whole new generationof microchips, surmounting basic physical constraints limiting thefurther development of ever-smaller, ever-faster silicon chips.Graphenecould also substitute for copper to make the electrical connectionsbetween computer chips and other electronic devices, providing muchlower resistance and thus generating less heat. And it also haspotential uses in quantum-based electronic devices that could enable anew generation of computation and processing.The mobility ofelectrons in graphene -- a measure of how easily electrons can flowwithin it -- is by far the highest of any known material. So is itsstrength, which is, pound for pound, 200 times that of steel. Yet likeits cousin diamond, it is a remarkably simple material, composed ofnothing but carbon atoms arranged in a simple, regular pattern.
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