Researchers model graphene for use in the real world

Work by scientists in the US on linking graphene to metal connectors paves the way for realistic electronic designs.

In a bid to bridge the gap between the lab and the fab, researchers in the US are working on understanding the complex interactions in the junctions between Wundermaterial graphene and the metal connectors that would hook it up to the rest of a circuit.

Graphene, a two-dimensional form of carbon with a long list of seriously amazing properties , has huge potential for use in electronics. But as Salvador Barraza-Lopez, assistant professor of physics at Georgia Tech, said in a statement, "If you want to use graphene for devices, you want to understand what will happen with metal contacts".

The problem is that metals will form covalent bonds with graphene and ruin all its special electronic properties

According to an announcement from the University of Arkansas and Georgia Tech, people working on graphene research tend to assume that the connectors would also be made of doped graphene.

But in the real world, these connectors would be metal, which rather spoils the party. The problem is that metals will form covalent bonds with graphene and ruin all its special electronic properties. So if you want to make this stuff stick in real-world circuit design, you have to take this into account.

"So, we thought it was important to calculate the transport of electrons going beyond the assumption that the contacts themselves are doped graphene," Barraza-Lopez said.

Titanium-graphene junctions

The team wanted to build an accurate model of the way electrons move through titanium-graphene junctions, so they brought to bear the power of quantum mechanics, and state-of-the-art computational power.

According to the announcement: "Within quantum mechanics, the electrons at these graphene-metal junctions behave much like a light beam does when it is shone on a crystal — some of the light scatters and some of it goes through. For graphene junctions the electronic transparency of the material indicates how many of the electrons on one contact make it through the other metal contact."

The researchers describe their work as the "most accurate" model of the electronic transparency of realistic graphene-metal junctions available to date. They hope the work will allow for "realistic design of potential electronic devices".

The paper is published in the journal NanoLetters.