Professor Pertti Hakonen ended up specializing in low temperature physics under the guidance of academy professor Olli V. Lounasmaa and later, from the 90’s, in nanophysics with the inspiration from Professor Mikko Paalanen. Nowadays professor Hakonen leads the Low Temperature Laboratory’s Nanogroup that employs ten researchers. The Nanogroup as well as the Low Temperature Laboratory as whole is known for its world class research.

Prof. Hakonen coordinates the EU funded CARDEQ-project that collects seven groups doing front line carbon nanotube research. The goal of the project is to develop a very sensitive mass detector with a sensitivity of one atom. The detector is based on a freely hanging carbon nanotube. Due to their light weight, carbon nanotubes are more sensitive mass detectors than metallic or silicon based nanoresonators. During the recent year the goal of the project has evolved to include grapheine as a potential material for the sensor.

- The competition in the field of nanotube resonators is tough. Our project reached atomic scale mass resolution in the beginning of the summer, but we got little late in publishing the results. Alec Zettl’s group from Berkeley (University of California) managed to publish their results on the same topic just before we did, frowns Pertti Hakonen.

In collaboration with Nokia in a joint Nanosystems-project the group is developing so called ballistic transistors and studying the use of grapheine in their fabrication. The goal of the research is to develop new technologies to mobile devices that enable the increase in the speed of operation with smaller power consumption.

- Grapheine was not found until 2004 and is at the moment a very expensive material. When the manufacturing methods improve we can expect the decrease of the price due to the mass fabrication. So far, also we use so called “scotch method” where the grapheine, which is actually a single atom layer of carbon, is produced by peeling one atom layer of carbon by hand. Grapheine is a very promising material for electronics and with decreasing price it will be a competitive alternative for silicon, at least in certain special applications, Pertti Hakonen envisions.

The goal of the grapheine research is to fabricate narrow nanostrips of grapheine that are of equal width and where the energy gap is controlled by the width of the strip. The biggest challenge at the moment is the control of the border regions of these nanostrips. This kind of problem does not exist in carbon nanotubes, since they are tubes as their name implies. On the other hand, the connections between the elements are easy to fabricate in graphene unlike with carbon nanotubes.

The energy gap reachable in grapheine is significantly lower than in conventional semiconductors. For mobile electronics this is a clear advantage since it allows clear savings in the energy consumption.

- At the moment grapheine is studied all over the world and sometimes it feels that it could be more beneficial to study carbon nanotubes in more detail. Microwave region would be an interesting direction in the carbon nanotube research Pertti Hakonen states. However, in the competition for the funding it could be difficult to acquire funding to non-mainstream research and, after all; grapheine is a very interesting new material.

A successful research group must have international contacts with the universities doing world class research. The contacts of the Nanogroup are mainly in the Europe but there are intentions to start collaboration with for example Cornell University, where the researchers managed recently to fabricate nanoresonators from graphene. Additionally, the group has collaboration in theoretical aspects with Landau-institute in Moscow.

The Nanogroup collaborates with VTT in the Center of Excellence in Low Temperature Quantum Phenomena and Devices in the development of SQUID-amplifiers. SQUID sensors (Superconducting quantum interference devices) are for measurements of tiny magnetic fields or electric currents. The sensors are operated at cryogenic temperatures near 4 Kelvin achievable by liquid helium or modern cryocoolers. VTT has especially strong competence in microwave region.

- The third version of the SQUID-amplifier that we have developed in collaboration with VTT and a VTT spin-off Aivon Oy is being introduced to the markets at the beginning of the next year. We hope that Aivon will be able to penetrate the markets with that, says Pertti Hakonen.

A few years ago the superconducting quantum-bit developed by the Nanogroup was awarded a patent which was immediately sold forward. The actual benefit of this invention is expected to be gained at the earliest within the next 20 years, most probably in cryptographic devices.

- Next, our group will study the possibilities to combine quantum bits and mechanical resonators. Behind this research is, of course, the competition to beat the quantum limit in actual mechanical systems, states Pertti Hakonen.