Published: 28.01.13

How graphene behaves on a small scale

ETH Zurich is involved in the “Graphene Flagship” project through Klaus Ensslin, a professor of experimental physics. ETH Life spoke to him about the advantages of graphene and his personal vision of this very special material.

Interview: Fabio Bergamin
Klaus Ensslin, professor of experimental physics at ETH Zurich, and his group are part of the Graphene Flagship Project. (Image: Heidi Hostettler / ETH Zürich)
Klaus Ensslin, professor of experimental physics at ETH Zurich, and his group are part of the Graphene Flagship Project. (Image: Heidi Hostettler / ETH Zürich) (large view)

Professor Ensslin, the European Commission has chosen graphene research for one its two flagship projects. What makes the material so special as to have a major research project devoted to it?
Graphene is unique. It is a thin material, a sort of film, and consists of a single atomic layer of carbon. It is the most conductive material known today. At the same time, it’s transparent, harder than diamond and combines seemingly contradictory properties such as maximum elasticity and maximum tensile strength. What’s more, it is relatively cheap to make. Graphene is regarded as a miraculous material with enormous potential for science and applications.

What might these applications be?
Already this year or next, there’ll be Smartphones on the market with touchscreens based on graphene instead of indium tin oxide. Indium is toxic and stocks soon dwindle. Graphene can be used as a touchscreen because it’s both conductive and transparent. This application is already at a very advanced stage of development. Other possible future applications might be conducting strips on computer chips and graphene as a material for batteries and solar cells or a lightweight material for aircraft. The list of potential applications is long and goes beyond engineering into biology. With the flagship project, the EU is ultimately trying to give the European economy a leading role in the implementation of graphene technologies.

Where is there a need for research?
It is not only industrial research and materials science that concentrate on graphene these days; it is also about developing physical foundations or new synthesis methods, tackling environmental and health aspects or finding new applications for electronics. The flagship project has got eleven sub-projects that cover all this.

The “leading house” for the flagship project is the Swedish university Chalmers. They’ll be celebrating this evening, I take it. You are also involved in the project. How pleased are you?
Naturally, I’m delighted, too, no question. We have already “raised our glasses virtually” with a number of European colleagues via email.

What will your part in the project be?
Our team is involved in the subproject concerned with physical foundations. We’re interested in how the material behaves on a small scale, at the nano-level and taking quantum physics into account, which comes into play on this scale. The aim of our research is ultimately to develop novel systems with graphene – so-called quantum systems – that have unprecedented properties. Where the journey will take us and what concrete applications will result from this research remains to be seen. We conduct basic research. Our primary concern is to understand the physical and quantum physical properties of these quantum systems.

Can you give us an example?
We want to produce little islands of graphene on different substrates, for instance. Graphene has got a honeycomb structure, whereby the edges are relevant. We’re going to try to manipulate the edges in a targeted fashion and then study the electronic effects that are caused by these edges. This requires extremely sensitive measuring techniques, which we have developed in our group.

When will the flagship project get underway?
A lot is still unclear. Before the money from the EU reaches the individual research groups, the criteria for distributing the money among the project partners still need to be worked out, for instance. As far as I know, these criteria haven’t been finalised yet.

How will you use the money once it becomes available?
As with most research projects, the majority of the funding will go on personnel costs. In concrete terms, we will be able to boost our existing graphene team at ETH Zurich with some extra manpower.

And when can the first results of the project be expected?
That depends what you mean by results. The graphene community is already incredibly active. In recent years, the number of results and scientific publications in the field has skyrocketed.

What is your personal dream when you think about the future of graphene research?
Our goal is to develop a graphene quantum dot that contains an electron with a spin that remains stable for a long time. A quantum dot is an artificially constructed system that essentially behaves like an atom. It could be the unit for a future quantum computer. There are theoretical predictions that spins in carbon-based structures might be considerably more stable than in most semiconductor environments.

About the person

Klaus Ensslin (52) is a professor of experimental physics at ETH Zurich. He conducts research at the interface between quantum and classical physics, working on the development of new materials and their optimisation, especially their purity. Quantum structures are structures that behave in a similar way to individual atoms, photons or ions.
Ensslin is also the Director of the National Centre of Competence in Research “Quantum Science and Technology”. In a sub-project of this research association, several groups from ETH Zurich and the universities of Basel and Geneva are working on graphene-based quantum structures.

Reader comments: