Journal club

Laurence Eaves

University of Nottingham, UK

A semiconductor physicist sees graphene transistors as a triumph for small-scale research.

Reading about a major scientific breakthrough from a small university group always gives me particular pleasure. Funding agencies tend to favour big headline-grabbing initiatives, but many research successes in condensed-matter physics, such as the development of magnetic resonance imaging and polymer light-emitting diodes, have come from small groups funded initially by modest grants.

Recent work from Manchester University, UK, on the electronic properties of graphene further demonstrates what a small, dedicated team can achieve. In 2004, researchers there fabricated a transistor from a few atomic layers of graphite (K. S. Novoselov et al. Science 306, 666–669; 2004), a cheap and widely available material.

Why, I wondered, hadn't somebody thought about doing this before? And why were the electronic properties so good?

With the benefit of hindsight, one can see why it works. The Manchester team had the skill and patience to cleave graphite right down to a single atomic layer. An atomic sheet of graphite (graphene) contains few free electrons, so it is easy to control the current flow. Also, the electrons in graphene have a curious property: they move as though they have almost no inertial mass, so the device can act as a fast switch.

Recently, the same group showed that small ripples in graphene, like rucks in a carpet, scatter electrons via a subtle quantum effect (S. V. Morozov et al. Phys. Rev. Lett. 97, 016801 1–4; 2006). By improving their fabrication technique, the team succeeded in removing the ripples, enhancing further the device characteristics.

Longer-term, we should see new applications of graphene transistors in electronics. Funding agencies and policy-makers, please note!

Nature 442, 722-723(17 August 2006) | doi:10.1038/442722a; Published online 16 August 2006