It has been known for some time that the traditional silicon chip technology will run out of steam. The Moore’s Law increase in power versus decrease in feature size will bring us to a point where quantum effects will make traditional circuit design impossible. There is still headroom, but most people regard the silicon chip as being closer to its limit than to its origin.
But we have become very used to constantly increasing power. What could not be done five years ago can now be done, and we expect that to continue. It is not only scientific development that demands this, so does commercial computing and so, in fact, does the whole technology industry, which is powered by the constant craving for the ‘upgrade’.
The hunt has been on for some time to find a new basis for ‘chip’ technology. People have suggested biological or molecular computing. Quantum computing is being pursued vigorously by several important research groups around the world, but is probably too far off to fill the gap.
When new properties were found for carbon, a new stream of research was opened up. It started with Buckminsterfullerene and progressed to ‘nanotubes’, which showed promise for the Holy Grail of electronics – the ballistic electron. This is a structure where an electron can pass without any scattering.
One of the most important developments in this field was made by the team at Manchester University, led by Professor Andrew Geim. Geim is not a conventional scientist. He is more like the public perception of the ‘inventor’ who has an off-the-wall idea and tries it out. Sometimes it works, sometime it doesn’t. Geim decided to try and find out what would happen if a carbon nanotube were flattened out to make a fabric one atom thick. He managed to make one and discovered graphene, a material with all the properties required of the new generation of electronics.
This idea has been taken up by many research groups around the world, possibly close to 100. They are not limited to academic researchers. Companies such as Intel are very interested and are putting money into graphene research. It is very early days and nobody is prepared to say that this is the answer, but simple devices have been demonstrated and the field is regarded as probably the most important of the many competing fields looking for the successor to the silicon chip.
This is not the first time that Geim has had a major impact on solid state research. He enjoys what he calls ‘hit and run’ experiments, which just try out an idea. In the past, he has stopped at the first experiment and let others take the subject to much more advanced levels. He famously levitated a frog in a magnetic field; the photograph of the ‘flying frog’ went around the world and excited a lot of interest in magnetic levitation.
Lucky knack?
Later he made ‘Gecko Tape’, which mimicked the way that geckos cling to smooth surfaces. A piece of tape on a person’s hand would be strong enough to suspend them from the ceiling – Spiderman style.
Any one of his high-profile discoveries would have been enough to build a career on, but previously he has left it to others to develop them into a serious field of research. He has enjoyed the ‘renaissance scientist’ image, but has now decided that graphene is something he will concentrate on for many years, because of the wealth of fascinating properties he believes are yet to be discovered about it.
Professor Laurence Eaves from the Department of Physics at Nottingham University knows Geim well and his own group is researching magnetic levitation. He says: ‘He has a strong personality. He gives the impression of being a bit outspoken, but actually he plays a pretty straight bat.
‘He has a great knack of finding where the interesting areas are and he tends to find things that capture the public imagination. The flying frog was a well-known piece of physics. What he did was bring it out in a very practical and real way that captured not just the general public’s imagination, but gave the idea to other scientists, including myself, that there were other things we could do with magnetic fields, that was certainly inspirational.
‘The Gecko stuff resulted from his nanolab at Manchester, and it was a beautiful idea and it worked. The graphene thing really is an outstanding piece of work, scientifically as well as being of general interest. It really is a tour de force.
‘There is obviously more in his other stuff that other people have taken on, but graphene is something that he wants to carry on himself. It is clearly a very important discovery and the jury is out, but clearly it will lead to some interesting technology.’
Top grades at school
Geim was born in Sochi on the Black Sea coast of Russia. His parents were both engineers and he believes that his interest in technical subjects was inherited from them in some way. He was not a child prodigy, but he was always top of his class at school. He applied to study at university in Moscow and faced a difficult task. As he was Jewish he was regarded by many as someone who would simply leave the country after he received his education. He had to sit entrance exams and had to do exceptionally well to even be considered. He got the maximum grade in all 10 subjects.
He says: ‘It was extremely selective, and my nationality didn’t help. I was regarded as a potential emigrant who would leave the country, so I had to get the top marks in those exams to get in.’
He started at the Moscow Technical University at the age of 17 and worked hard. He says that getting an undergraduate degree in Russia is much harder than in most western countries, because the course is more comprehensive and goes into greater depth. He says he may have learned a lot more than he really needed to, but the course was so tough that many people simply dropped out, or even cracked under the strain.
He says: ‘The pressure to work and to study was so intense that it was not a rare thing for people to break and leave, and some of them ended up with everything from schizophrenia to depression to suicide. I would say that people work 10 times harder than in any UK university, even Oxford and Cambridge. Many of the things I learned I never used in my professional life, but I guess it helped develop some of my axial lobes. I used those lobes to replace the lobes I lost due to the amount of alcohol we needed to wipe out after the exams.’
One of the best things about being at university was it was a means of avoiding the compulsory two years of military service every Russian man has to undergo. This was not the only reason, but it was a bonus. He managed to relax by taking up mountaineering and still today he likes to relax by climbing.
He did well at university and decided to continue to a PhD and ended up in Solid State Physics in the city of Chernogolovka, just outside Moscow, more by accident than design.
He says: ‘I just went with the flow according to my exam results and someone put me by accident into a solid state group. If I had chosen, it would not have been my favourite. Probably like most people studying physics, I would have preferred particle physics or astrophysics. But after a few years of research you realise that those things that sound good are not really. I am so glad I am not doing astrophysics or particle physics, because what it actually means is that there are so many people involved in any experiment you are just a tooth in the wheel and, if you end up at the top of the food chain, it is more by luck than your abilities. Those at the top could just as well be journalists or politicians.
‘My PhD subject, metal physics, was so boring that I decided that I did not want to end up doing this for the rest of my life.’
He stayed at Chernogolovka for two years as a post-doc. By this time things were changing and the old Soviet Union was falling apart. Because his parents had German ancestry he had the chance to leave the country. He could have left earlier, but he would have had to cheat and Geim says he was always a conformist and did not want to do it like that. He was offered the chance to work at Nottingham University, in the UK, for six months as a visiting fellow and he decided to take it to gain some experience.
He says: ‘The people had the equipment and the time to do things and it was extremely interesting; the facilities were incomparable. The Soviet Union had a very good theory school, but it did not have the facilities to really do experimental research. It was a different world. At that time I determined to get a position in the west and leave Russia.’
He obtained a string of post-doc positions in Copenhagen, Bath and again in Nottingham. He said that, even though he was in temporary positions, his fellow researchers realised he was above the level of typical post-docs and he was given a lot of freedom to choose his own research ideas. He started studying small structures, long before nanotechnology was fashionable.
His first permanent position (equivalent to tenure in the US or a reader in the UK) was at the University of Nijmegen in the Netherlands. He put down roots here, eventually gaining Netherlands nationality. He eventually chose nano-scale superconductivity as his area of research. He achieved some success with many publications and invited talks.
He says: ‘Many people chose a subject for their PhD and then continue the same subject until they retire. I despise this approach. I have changed my subject five times before I got my first tenured position and that helped me to learn different subjects.’
The flying frog happened when he started looking for something new. He had always been interested in the magnetism of water, and the idea that water can be softened using a magnetic field. He tried putting water in a strong superconducting magnetic field and discovered it could be levitated. This surprised him and he wanted to find a way to demonstrate this in an interesting way. He decided that if water could levitate then a living organism, most composed of water, could also be levitated.
He had no idea how much impact his ‘flying frog’ photograph would have; it appeared in magazines and newspapers all over the world.
He says: ‘Water would have been spectacular, but we thought a live animal would have been even more spectacular. I was not surprised by the reaction of lay people, but I was surprised there are so many cranks and crackpots around. We were getting letters from crackpots for years claiming we had proved the existence of everything from god to UFOs. It was on everything from the BBC to CNN to the newspapers in Iran and Mongolia. It did lead to a number of papers and there are probably now about a dozen groups working on magnetic levitation around the world. There are still people around who are not very happy with the way I popularised the subject because it was some kind of vulgarisation of their serious research. It did bring a lot of research funding to Nijmegen, because the government loved the story.’
He stayed six years at Nijmegen and was eventually promoted to full professor, but eventually became unhappy. He found the academic system in the Netherlands very hierarchical and stilted. He felt that professors treated other scientists at his level as if they were technicians rather than true scientists in their own right so he started looking for another position.
He says: ‘I left because I think my sense of humour was not the same as the academic community in the Netherlands.’
He received many offers from around the world, including top positions in the Netherlands and in top US institutions, but the one that caught his attention was the offer to replace Professor Henry Hall as head of solid state physics at Manchester University. He had enjoyed his previous times in England and thought it would suit him best. His wife was also offered a position to move to Manchester with him. He has no regrets about moving and has found his new surroundings to be better than he could have imagined, apart from the wet Manchester weather!
He soon attracted enough research funding to set up a centre for Mesoscience and Nanotechnology, which although still small, he says is up to the same level as any other in the world.
Sticking power
He could not stay away from the public eye and when he read in a journal that scientists had worked out how the gecko manages to grip smooth surfaces, he set out to design a tape with the same features.
He says: ‘Gecko tape was a sideline. I simply cannot keep to the same track in my research. It is very difficult to get research money for something new. You have to ask for money to continue something that is old, but I believe you should use some of the money to try something new. We never had enough money to make enough tape to put a student out of a window. I always try to do “hit-and-run” experiments and usually they fail.’
Graphene started as one of these hit-and-run experiments. He had read a lot about carbon nanotubes and the stories that they would revolutionise everything.
He says: ‘When you have a thousand people researching one subject, they start acting like a single organism that acts by its own rules. We just wanted to say; let’s take a very thin slice of graphite and see if you get a material like carbon nanotubes because we wanted to study this material. What we never expected is that we could slice it into a single atomic layer – it should be impossible. With the benefit of hindsight you can say that it is because of the chemistry of carbon, but there are theoretical principles that say that two dimensional materials cannot exist, because of the movement of atoms in the crystal lattice are usually too violent.
‘At low temperatures everything is possible, but this existed at room temperature. With the benefit of hindsight it was obvious that graphite existed in three dimensions and could be one or zero dimensions in fullerene or one dimension in nanotubes. We were just lucky to be the first to find the two dimensional version, which is actually the basic constituent of all the others.
‘It is always nice to find a new class of material, but what really excited people was that the material is of very high quality and despite being only one atom thick it cannot be cut with a diamond knife. At the same time it is exposed to the environment from both sides and yet electrons will move through it without any noise.’
Once his results were published, research on graphene exploded throughout the world. There were groups working along similar lines and could have come up with the same idea eventually, but Geim was the first to publish and, whether he sought it or not, got the glory. There are now anything up to 100 groups doing graphene research. Geim has even been working with his old institute in Chernogolovka, which succeeded in creating a transistor based on graphene and it is expected that work to be published soon will show that it is possible to make logic gates.
Geim does not claim to have discovered the new basis of electronics. He realises that there is so much more work to do before we can even speculate about the real applications of this material and there have been many false dawns in science. But he understands that there is a strong economic imperative to find some way of overcoming the limitations of silicon electronics and that governments and technology companies understand the importance of graphene in this process.
For the first time he has decided that graphene has the potential to keep him on the straight and narrow for many years to come and he will make it his single track of research for at least 10 years.
Having said that, it is hard to imagine his mind not wandering a little, and who knows what he will come up with next? Graphene will be a hard act to follow – maybe next time it will be warp drive?
John Murphy
Education
1982 graduated with honours from the Moscow Technical University
1987 PhD at the Institute of Solid State Physics, Chernogolovka, Russia
Professional Positions
1987-1989 Research Scientist at the Institute for Microelectronics Technology, Chernogolovka
1990-1991 Royal Society Visiting Fellowship at Nottingham University, England
1991 Visiting Researcher at the Ørsted Institute, Copenhagen, Denmark
1992 Research Officer, University of Bath, England
1993-1994 Research Associate, University of Nottingham, England
1994-2000 UHD (Associate Professor), University of Nijmegen, the Netherlands
1998-2000 Special Professor (honorary) at University of Nottingham, UK
2000 Professor, University of Nijmegen, the Netherlands
since 2001 Professor of Physics, University of Manchester, UK
since 2002 Director, Centre for Mesoscience and Nanotechnology, University of Manchester