Keywords: energy (316) solar energy (252) materials research (72) personnel (248)

News    17.10.2014

HZB Freigeist Fellow Dr. Annika Bande

HZB Freigeist Fellow: Dr. Annika Bande
Foto: Mirko Krenzel for VolkswagenStiftung

As of early October, the HZB is home to one of the Volkswagen Foundation's Freigeist Fellows: Dr. Annika Bande recently joined Prof. Dr. Emad Aziz' institute "Methods for Material Development". There she will build up her own junior research group with initially three PhD students.

The theoretical chemist's research focus is on ultrafast energy transfer processes. Central to her research is what's known as interatomic Coulombic decay (ICD) where an electronically excited state is produced within an atom. Upon returning to its ground state, the atom transfers its excess energy to a neighboring atom or molecule through electronic Coulomb interactions. During this process, the electrons interact with each other even over long distances.

These ultrafast energy transfer processes have already been studied both theoretically and experimentally, including at the HZB, in a number of variations in atomic and molecular systems. As part of her theoretical work, Annika Bande was able to demonstrate that ICD must also be taking place in semiconductor nanocrystals called quantum dots. Furnishing experimental evidence is what Bande and her team is hoping to accomplish as part of her work with Emad Aziz' institute. In a unique approach the scientists observe the electrons' motion in calculations and with various types of spectroscopy. From this they expect numerous direction-giving contributions to the investigation of chemical processes and to materials' research.

"Here at the HZB, I encountered optimal conditions for experiments being done that support my theory," Annika Bande says. The Aziz group has already conducted ICD investigations on atomic systems in aqueous solution. Adds Bande: "I'll be able to build on this experience while also broadening the instutute's spectrum as I'll be focusing my own work mostly on quantum dots." The scientist, who is currently working on earning the title of 'professor' at Heidelberg University, expects this will help her glean insights that will prove relevant to future solar cells, among other things.

The 790,000 Euro Volkswagen Foundation's Freigeist Fellowship provides funding for a five-year period during this initial phase. According to the Foundation, funding is granted to "exceptional researchers who have already earned their doctoral degrees and whose goal it is to move between established research areas while conducting cutting-edge, 'risky' science."

Hannes Schlender


           



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