Division of Materials Physics

The division carries out research in three different fields: nanostructures and ion beam analysis, electronic structures and microtomography, and electronics. The total number of scientists employed by the division in 2009 was about 50, including 7 professors.

Laboratory for nanomaterials and ion beam analysis

The experimental research activities employing ion- and cluster beams were continued successfully in the fields of nanostructures, ion beam irradiation and characterization. The Facility for Nanostructure Deposition (FANADE) came into full operation providing cluster ions of several elements. Low energy electron diffraction (LEED) and Auger electron spectroscopy (AES) hardware has been installed at the FANADE cluster deposition facility and complementary software for data acquisition and remote control is being developed. The spectroscopic techniques enable in-situ analytical and structural characterization of nanocrystalline materials formed by nanocluster deposition. A new substantial research facility in the laboratory for nanomaterials is the Cryogen-Free Dilution Refrigerator System received at the end of the year. Its commissioning will be, however, delayed till autumn 2010 due to the renovation of the laboratory premises.

Preparation for the foreseen accelerator building renovation in 2010 required much attention already in 2009. Despite of this fact, routine operation of both accelerators (TAMIA and KIIA) was possible. Two short tank openings were necessary at TAMIA. After an improved spark protection system was installed in May, no failures of the remote-control electronics inside the HV terminal occurred. At the 500-keV accelerator (KIIA), a similar automation and control system was tested to locate corona problems.

The extension of the simulation activities into an entirely new area, namely simulation of vacuum arcing, started to bear fruit in 2009. Combined particle-in-cell and molecular dynamics simulations allowed for the first time to predict the surface damage produced by electrical arcs based on quantitative simulation models, and showed very good agreement with dedicated experiments carried out at CERN and the laboratory of nanomaterials. At the same time, the other long-running activities of the simulation team continued to produce outstanding results. For instance, simulations in our group combined with dedicated experiments carried out in San Diego showed that even pure metals can sputter chemically, in clear contrast to conventional wisdom. Classical and quantum mechanical calculations of the energetics of carbon on the surface of and inside metal nanoparticles and corresponding experiments showed that the radius of curvature of metal nanoparticles has a crucial role in carbon nanotube growth.

Laboratory of electronic structures and microtomography

The use of synchrotron radiation as well as the versatile X-ray instrumentation in our laboratory within materials science stayed in the research focus. A shift of the research emphasis to disordered materials can be observed while studies of liquid structures and liquid-solid phase transitions have been increased. The new imaging opportunities via the new X-ray microtomography instrument capable of micron resolution have opened new multidisciplinary projects in evolutionary biology, pharmacy, geology and paleontology, for example. The imaging opportunities have also greatly expanded ongoing studies on the properties and hierarchical structures of wood and other renewable materials. The experimental work is accompanied by strong computational activities which have played an important role in strengthening the fundamental understanding of electronic structure behind the macroscopic properties of materials via experiment-theory interaction.

Electronics

We develop novel measurement methods and sensors combining ultrasonics, optics, laser-acoustics, electronics, and advanced signal processing for industrial and scientific applications.

Linking micro- and nanoscale structural properties to macroscale mechanical strength has occupied us.

Ultrasound assisted tissue engineering has been of interest as has the development of our advanced optical tweezers instrument in collaboration with the Institute of Biotechnology, Univ. of Helsinki, and the Harvard Medical School.

A microelectronics (ESAIL) production line was developed together with the Finnish Meteorological Institute. We aim to build the largest and fastest vessel known to man. New collaborative enterprises were successfully continued or started with partners from academia and industry, including research on mechanical pulping energy efficiency in collaboration with VTT and development of toolmark identification with NBI, - the CSI Helsinki case.