"We want our graphene to sit on something insulating, because we are interested in studying the properties of the graphene alone. For example, if you want to measure its resistance, and you put it on metal, you're just going to measure the resistance of the metal because it's going to conduct better than the graphene."
Unlike silicon, which is traditionally used in electronics applications, graphene is a single sheet of atoms, making it a promising candidate in the quest for ever smaller electronic devices. Think going from a paperback to a credit card.
"It's as small as you can shrink it down," LeRoy said. "It's a single layer, you'll never get half a layer or something like that. You could say graphene is the ultimate in making it small, yet it 's still a good conductor."
Stacked upon each other, 3 million sheets of graphene would amount to only 1 millimeter. The thinnest material on Earth, graphene brought the 2010 Nobel Prize to Andre Geim and Konstantin Novoselov, who were able to demonstrate its exceptional properties with relation to quantum physics.
"Using a scanning tunneling microscope, we can look at atoms and study them," he added. "When we put graphene on silicon oxide and look at the atoms, we see bumps that are about a nanometer in height."
While a nanometer a billionth of a meter may not sound like much, to an electron whizzing along in a grid of atoms, it's quite a bump in the road.
"It's basically like a piece of paper that has little crinkles in it," LeRoy explains. "But if you put the paper, in this case the graphene, on boron nitride, it's much flatter. It smooths out the bumps by an order of magnitude."
LeRoy admits the second effect achieved by his research team is a bit harder to explain.
|Contact: Daniel Stolte|
University of Arizona