\nBy Roger Highfield, Science Editor
\nLast Updated: 2:15AM GMT 02 Mar 2007\n<\/p>\n
Researchers have created the world\u2019s thinnest sheet – a single atom thick – and used it to create the world\u2019s smallest transistor, marking a breakthrough that could spark the development of super-fast computer chips.<\/p>\n
This innovation will allow ultra small electronics to take over when the current silicon-based technology runs out of steam, according to Prof Andre Geim and Dr Kostya Novoselov from the University of Manchester.<\/p>\n
They reveal details of transistors that are only one atom thick and fewer than 50 atoms wide in the journal, Nature Materials.<\/p>\n
In recent decades, manufacturers have crammed more components on to microchips, with the number of transistors doubling every two years. But the ability to cram in more components is now decreasing.
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\nTwo years ago, Professor Geim and colleagues used graphite to find the real-world equivalent of a super-simple material that for the past half-century has been known only to theoreticians: a two-dimensional crystal – a single sheet of atoms. So called graphene is a gauze of carbon atoms resembling a chicken wire.<\/p>\n
Graphene behaves as if the electrical current is not carried by normal electrons but by charged particles with no mass at all – when at rest akin to photons of light but which carry electric charge.<\/p>\n
Graphene brings scientists close to ballistic transistors – ultimately faster than any current technology.<\/p>\n
\u201cA ballistic transistor is one in which electrons can shoot through without collisions, like a bullet,\u201d he said.<\/p>\n
The first graphene-based transistor was reported by the team at the same time but it was not practical.<\/p>\n
Now the team has made the first graphene-based transistors suitable for use in future chips.<\/p>\n
Prof Geim does not expect graphene-based circuits to come of age before 2025 but argues it will probably be the only viable way to shrink microelectronics after the silicon era comes to an end.<\/p>\n
Working with the Dr Jannik Meyer of the Max-Planck Institute in Germany, Prof Geim also announces today in the journal Nature the first free hanging graphene sheet, a feat that had been thought to be impossible.<\/p>\n
They report that free graphene is not perfectly flat but instead crumpled and this ‘waviness\u2019 may be responsible for the unexpected stability of these extremely thin carbon membranes.<\/p>\n