"There are not many places on earth where you can investigate this like you can here"

Research in other countries, build up your international network: completely in the spirit of the natural scientist Alexander von Humboldt, there are currently two researchers with a Humboldt Research Fellowship working simultaneously in the KiNSIS priority research area with Dr Gitanjali Kolhatkar and Dr Chao Li.

One of the most modern scanning tunnelling microscopes in the world is certainly worth a trip to Kiel. Its fine needle tip scans the surface of a material sample with nanometre precision. This makes it possible to not only depict individual atoms on surfaces, but also to move them.

For over a year, Dr Chao Li has been researching under Professor Richard Berndt at the Institute of Experimental and Applied Physics (IEAP). With this equipment, and in collaboration with other working groups, he wants to better understand and manipulate the magnetic properties of molecules, known as their "spin". "We have already been able to discover some magnetic molecules and specifically change their spin," said the physicist from Peking University. If molecules are switched back and forth between two different spin states, this can be used to process information, similar to the binary code of 0 and 1 in a computer. Such switchable molecules could lay the foundation for smaller data storage and new kinds of quantum computers.

Dr Gitanjali Kolhatkar is also partly involved with storage processes, such as those in computers or mobile phones. She completed her doctorate in Montreal, Canada, before joining the Institute of Electrical Engineering and Information Technology as a Humboldt Research Fellow in October 2019. Since then, she has been conducting research under Professor Hermann Kohlstedt, especially into the material aluminium scandium nitride (AlScN), which was developed at the CAU. It is one of the ferroelectric materials, which means that it is permanently electrically polarised. If an external electrical signal is introduced, the crystal structure of the material changes at the atomic level - and thus its electrical polarisation as well as its properties. "I want to find out how I can change the characteristics for different applications in a targeted manner, for example for data storage," said Kolhatkar to sum up her goal. In cooperation with the working group led by Professor Kai Rossnagel, which is also based at the IEAP, she investigates AlScN using high-intensity X-rays at the Deutsches Elektronen-Synchrotron (DESY) in Hamburg. She thereby wants to examine, among other things, what happens in the material during the change process. "There are not many places on earth where you can investigate the electronic structure of materials as precisely as you can here. The Fellowship helps me to expand my network and to initiate international collaborations," said Kolhatkar. Her boss in Montreal was also a Humboldt Research Fellow, and advised her to pursue the research stay with Kohlstedt at the CAU. Chao Li’s doctoral supervisor also recommended that he apply for a Fellowship in Berndt’s working group, after researching there himself.

 
Both Kolhatkar and Li have noticed differences to the university systems in their respective countries. For example, researchers in China focus primarily on particularly fast or hard work in order to achieve scientific breakthroughs. However, this often leads to research questions being tackled in a rather one-sided manner, is Li’s impression: "It seems to me that research is more long-term and in-depth in Germany." Kolhatkar finds it especially striking that Master's students in Canada already do a lot of work in the laboratory, but are also left to fend for themselves more. Work aside, in Germany she sometimes misses the wide open landscapes of Canada, but at the same time, she likes the "vibe" of the closely-spaced European cities. Before Li came to Schleswig-Holstein, he did not know how beautiful and peaceful Kiel is. He particularly enjoys going for a walk along the waterside. But he still has one wish for the city, he admitted with a smile: "More Chinese restaurants."

Author: Julia Siekmann