Scientists Probe Electronic Properties Of Graphene

Scientists from Manchester University have taken a step forward in their studies of graphene – a revolutionary substance made from a single layer of carbon atoms, which could be used to build the next generation of mobile phones and computers.

Graphene atoms are arranged in a honeycomb-shaped, hexagonal lattice and, although the substance is chemically very simple, it is also extremely strong and conductive. Because electrons travel a lot more quickly in graphene than they do in silicon, graphene has been touted as a replacement for traditional semiconductors in PC and gadgets.

Electronic properties

Graphene was first discovered by scientists at the University of Manchester in 2004, when Professor Andre Geim and Professor Konstantin Novoselov used Scotch tape to peel away layers of carbon from a piece of graphite (pencil lead). The two professors were awarded the Nobel Prize for Physics in 2010 for “groundbreaking experiments regarding the two-dimensional material”.

According to the scientists, writing in the journal Nature Physics, electrons in graphene mimic massless relativistic particles – such as photons – giving them unique electronic properties.

In the latest experiments, researchers suspended sheets of graphene in a vacuum – which provides the optimum conditions for electrons to flow through the material. The vacuum prevents electrons from “scattering”, thus enhancing the effect of electron-on-electron interaction. This is the first time the interactions between electrons in graphene have been clearly seen.

“Although the exciting physics which we have found in this particular experiment may have an immediate implementation in practical electronic devices, the further understanding of the electronic properties of this material will bring us a step closer to the development of graphene electronics,” said Novoselov.

Faster, greener devices

Research institutes and universities around the world are already looking at ways to build devices such as touchscreens, ultrafast transistors and photodetectors using graphene. Earlier this year, IBM delivered the first wafer-scale graphene integrated circuits, that are smaller than a pinhead and heighten the sensitivity of current wireless devices.

Graphene also possesses superior electrical, optical, mechanical and thermal properties that could make it less expensive and use less energy inside portable electronics like smartphones. The University of California recently has created a miniature optical device that could enable the large data files for 3D movies to be downloaded to a smartphone in seconds.

“Graphene enables us to make modulators that are incredibly compact and that potentially perform at speeds up to ten times faster than current technology allows,” said Professor Xiang Zhang in May. “This new technology will significantly enhance our capabilities in ultrafast optical communication and computing.”

Meanwhile, a team at Illinois University has discovered that graphene may be a self-cooling material that could result in the production of more efficient and energy-saving devices.