TU Wien has awarded the Hannspeter Winter Prize to physicist Elisabeth Gruber for her research into the bombardment of surfaces with highly charged ions.
The conditions created by Elisabeth Gruber in the laboratory are often so extreme that you would struggle to find them anywhere else in the entire universe. Her research looks into the impact of highly charged ions on different surfaces, which has allowed her to uncover the answers to questions that are crucial within a wide range of applications, such as microelectronics, material characterisation and even cancer research. And now she has been awarded the TU Wien Hannspeter Winter Award for her work on her PhD thesis, supervised by Prof. Friedrich Aumayr (Institute of Applied Physics, TU Wien).
Ions and surfaces
Elisabeth Gruber conducted many different experiments while working on her thesis. The initial stage involved applying a great deal of energy to remove a large number of electrons from heavy particles, such as xenon atoms. This gives rise to highly charged ions with a positive charge of up to 44, which can then be accelerated, aimed at a particular material and shot at it.
"There can be all sorts of effects when the ions come into contact with the material in this way," explains Elisabeth Gruber. "This is dictated by a number of parameters, ranging from the projectile type, charge and energy, to the material in question and even the angle of impact."
For example, when the ions impact upon a crystal, their energy can be transferred to the crystal atoms, potentially causing a small area of the crystal to melt or even evaporate. This method can be used to create specific structures featuring nanoscale hillocks and trenches on the surface of the crystal. "This is also interesting because it shows us how materials can be damaged by inadvertent ion bombardment - take electronic components in satellites, for example," says Elisabeth Gruber.
Most notably, Elisabeth Gruber uncovered exceptional results when experimenting with graphene - a form of carbon that consists of just a single layer of atoms. Highly charged ions penetrate the graphene layer and pick up a large number of electrons, causing a temporary shortage of electrons in the graphene at the point of impact. However, this can be rectified at astonishing speed, as the graphene is able to supply electrons from elsewhere on a femtosecond time sale. This results in extremely strong electric currents, which would not be possible under normal circumstances.
"The huge number of scientific publications to which Elisabeth Gruber made a significant contribution whilst working on her thesis alone is notable," says her PhD thesis supervisor Friedrich Aumayr. "In addition to that, she designed and set up major parts of her experiments herself and supervised a number of diploma and bachelor students with success too."
Elisabeth Gruber comes from South Tyrol, where she won a prize as one of the top ten high-school graduates for her results back in 2006. She then went on to study physics at TU Wien. In 2012, she wrote her diploma thesis on bundling ion beams using glass capillaries at the Institute of Applied Physics, where she began her research into highly charged ions and their interaction with surfaces. This work saw her form plenty of close ties with research groups abroad and she spent extended periods away from home, researching at the Helmholtz-Zentrum Dresden-Rossendorf in Germany and at the heavy ion accelerator in Caen in France as well as at the University of Duisburg-Essen and at Bielefeld University, both in Germany. Having completed her doctorate, Elisabeth Gruber took up a postdoctoral position at Aarhus University in Denmark in September 2017.
The Hannspeter Winter Award for outstanding young female scientists
The Hannspeter Winter Award is presented to one female doctoral graduate of TU Wien every year, with the winner receiving EUR 10,000 funded jointly by TU Wien and the BA/CA Foundation. The research prize was established in honour of Prof. Hannspeter Winter, who was a persistent advocate of young female scientists.
This year sees the Hannspeter Winter Award go full circle, as it is the first time it has been awarded to a graduate from the Institute of Applied Physics, which is where Hannspeter Winter worked until his death in 2006. Our winner even attended the physics introductory lecture given by the man himself during her first few weeks at the university. After Winter sadly passed away, Friedrich Aumayr stepped in to give that lecture and would later go on to become Gruber’s PhD thesis supervisor.
 Photo: Klaus Ranger Fotographie