Graphene – that’s got something to do with pencils right?
Close, but graphene is capable of slightly more than a humble pencil lead. Graphene is something of a wonder material with uses in fields ranging from nanotechnology to electronics. The carbon-based material is poised to transform the world of computing – by making screens that can bend like paper, turbo-charging the internet and maybe, one day, making pocket-sized supercomputers possible.

Graphene is a carbon-based material tipped as a breakthrough in material science, nanotechnology and electronicsImage: CORE-Materials
Sounds like something of an overachiever – but is any of this likely to happen in my lifetime?
One of the first graphene-based technologies likely to find its way into your pocket is the flexible display. Researchers have already made a transparent graphene touchscreen that can be rolled up like a piece of paper.
Early graphene screens range in size from mobile phone displays up to screens as large as a home TV. The material is a natural choice for a flexible touchscreen because it is very thin – a sheet of carbon just one atom thick – is tougher than steel and conducts electricity extremely easily. Graphene is so pliable that researchers have demonstrated that transistors made out of the material could be stretched by up to five per cent and still work as expected.
Surely graphene can do more than just make bendy screens?
Indeed it can. Graphene also looks to be a very promising material for supercharging the speed at which information can travel over the internet.
Researchers at the University of Manchester found that binding tiny metallic structures to graphene produces a twentyfold increase in the amount of light it can harvest and turn into electrical energy. This excellent light-gathering ability, combined with the high conductivity of graphene, could lead to cables that are able to transmit information tens or hundreds of times faster than those found in networks today. Modifying graphene in this way could also produce solar cells that are able to convert a high percentage of the energy that hits them into electricity.
What about these pocket-sized supercomputers then?
Graphene could one day provide a superfast alternative to silicon inside computer chips. However, there is a problem: graphene has difficulty switching off. Modern computers process information using microprocessors made up of billions of transistors. These transistors are able to switch electric circuits on and off to represent information. Unlike silicon-based transistors, graphene-based transistors are very difficult to switch off, and until this problem is solved, graphene transistors will be unable to take silicon’s place inside computer processors.
Experiments are taking place to add impurities to graphene to make it a better switch, and if researchers can resolve this problem then the speed of computers with graphene-based processors could put today’s silicon-based machines to shame.
Thanks to its low electrical resistance, graphene can conduct electricity at high speed, giving it the ability to switch transistors on and off extremely quickly. These properties allow graphene transistors to hit speeds running into hundreds of GHz that would cause silicon-based processors to burn out. In April this year, IBM showed off a graphene-based transistor running at 155GHz, compared with up to 40GHz for similarly sized silicon transistors. Graphene’s low resistance also means that graphene-based chips would waste far less power as heat.
Before graphene transistors find their way inside microprocessors, they could find a use in a wide range of communication applications – such as signal amplifiers for mobile phones or radar – where graphene’s limited switching abilities are not so much of a problem. Graphene’s properties also make it a candidate for developing new gas sensors, DNA sequencers and components in the emerging computing field of spintronics.
So I shouldn’t expect a graphene microprocessor in time for the iPhone 5 then?
I wouldn’t get your hopes up. A researcher studying graphene at Cambridge University recently told silicon.com’s sister site ZDNet UK that it could take another 10 to 20 years before graphene replaces silicon inside computer chips. Official support might help things along though – the government recently pledged £50m to support research into graphene-based technologies.