Female scientist working in a lab with quantum magnetometry together with a male colleague
© Fraunhofer IAF
Baden-Württemberg has a high density of top researchers in the field of quantum technologies, among them Dr. Luo Tingpeng who works at Fraunhofer IAF in Freiburg.

Bringing quantum sensors to the people

Dr. Luo Tingpeng works at Fraunhofer IAF in Freiburg, where she carries out research on diamonds for applications in quantum magnetometry. Baden-Württemberg offers the Chinese-born scientist excellent conditions and top-class networks.

When Luo Tingpeng first stepped into her lab at the Fraunhofer Institute for Applied Solid State Physics (Fraunhofer IAF) in Freiburg in 2018, she found herself in an empty room. At the time, the institute was specialised in compound semiconductors, and quantum technologies were only in their infancy there. Luo’s group, ‘Quantum Sensors’, was new and extremely innovative. The researchers there work on laser threshold magnetometry. The idea behind this is a sensor that uses a diamond with optically active nitrogen-vacancy centres as a laser medium. The theory underpinning the research was developed a few years previously by Dr. Jan Jeske, who heads up the group. “Now the aim of our group is to find methods and materials to translate the concept into practice”, explains Luo.

A look inside hundreds of diamonds

Nowadays, Luo Tingpeng’s lab is equipped with modern measuring technology, including an optical table with all kinds of lenses, mirrors, prisms and lasers. She has already used the equipment to look inside many hundreds of diamonds. But the young scientist isn’t interested in shiny, perfect gems. Instead, she is looking for the defects in the diamonds’ grid structure. To be exact, she is on the lookout for nitrogen-vacancy centres or ‘NV centres’ for short. These NV centres have particular properties that make them potentially relevant for a large number of uses in quantum technology, including for ultra-fast quantum computers, in quantum cryptography and of course in quantum sensors.

Very promising for applications in medicine

Luo’s group takes advantage of the fact that NV centres are very sensitive to magnetic fields, making them suitable for use as extremely small sensors. This approach allowed for magnetic field strength measurements on the nanometre scale, something which was not possible before. Diamonds with a large concentration of NV centres can also be used to detect magnetic fields precisely. Another advantage compared to traditional magnetic field sensors, which need to be cooled cryogenically, is that NV centres work even at room temperature. “This makes NV centres in diamond such a promising material for medical applications, too”, says Luo. She is focusing in particular on potential applications in clinical imaging. “For example, I dream about magnetic resonance imaging that uses NV centres and can facilitate faster and much more precise diagnostics. Or it might someday be possible to detect brain activity as an improvement of magnetoencephalography (MEG) technology.”

Classifying and improving materials

But until that day, the job at hand is to classify the materials and refine them in such a way that they are perfectly tailored to the applications. As a result, Luo Tingpeng spent a lot of the first two years of her PhD sitting in the dark in the lab, looking for the right diamonds and determining their parameters. “We know now in theory what parameters the diamonds need to have. The next step is to find out how to work with the technology.” Her colleague Dr. Felix Hahl at Fraunhofer IAF is currently building a prototype for this purpose. The two researchers work hand in hand in materials development – a Chinese-German collaboration so to speak. “What we have in common is our curiosity.”

At home in Germany for ten years now

Luo Tingpeng came to Germany almost exactly ten years ago. She has spent most of this time in Baden-Württemberg. First, she was at Karlsruhe Institute of Technology (KIT), where she completed her Master’s in Optics and Photonics. After her external master’s thesis at what was then the Max Planck Institute for Biophysical Chemistry in Göttingen, she came to Fraunhofer IAF in Freiburg in 2018. The main factors prompting her return to Germany’s Southwest were the working conditions and the supportive environment at Fraunhofer IAF, but also Freiburg itself as a location. “I love this region – the weather, the culture, the lifestyle”, the young Chinese scientist enthuses, going on to say that the people there are warmer than elsewhere and very communicative. “Above all else, they are open to other cultures – I feel very accepted as a foreigner.” Luo Tingpeng also likes the close contacts between Germany and its neighbours France and Switzerland. “You feel like you are part of Europe.”

Good starting point for a scientific career

Baden-Württemberg is also an excellent location for Luo Tingpeng’s career as a scientist. “Baden-Württemberg has a high density of top researchers in the field of quantum technologies,” says Luo. In this context, she names Prof. Fedor Jelezko at Ulm University, with whose group at the Institute of Quantum Optics she collaborates, and Prof. Jörg Wrachtrup at the University of Stuttgart, who she cites as a “major role model”. Another advantage, she says, is that Baden-Württemberg’s state government is very supportive of quantum technologies, for example via the network QuantumBW. QuantumBW brings together a large number of partners from science and industry with the aim of working together to drive quantum technology research and bring it into application. “QuantumBW is a huge help for people and groups within quantum research to connect with each other even more. “For me as a young scientist, it allows me to forge good working relationships simply, even with very established experts in this field of research”, Luo emphasises.

Industry links to big players

According to Luo, another interesting aspect of the QuantumBW network is that it includes ten corporate partners, including big players like IBM, Mercedes-Benz, Bosch, Zeiss and Trumpf. “The proximity makes it easier to get in touch with those companies, creating good career and progression opportunities. And the aim of bringing research into application is in line with my own vision of bringing quantum technologies to people in their everyday lives. That’s really great.”

Pioneering research meeting pioneering companies

Luo Tingpeng will decide over the next few months how best to pursue this vision. Having completed her PhD with the distinction magna cum laude a few months ago, she is currently working on a large number of projects at Fraunhofer IAF. For example, she is involved in the lighthouse project NeuroQ by the German Federal Ministry of Education and Research (BMBF), which aims to control neural exoskeletons more precisely. Another project she participates in is Deutsche Brilliance (De-Brill), where Fraunhofer IAF collaborates with the start-up Quantum Brilliance in relation to the production process and new types of control techniques for diamond quantum computers.

In this context, Luo benefits from the fact that Fraunhofer IAF is leading in both quantum sensors and in research into quantum computers and also has strong links to industry. “At the moment, I am exploring and helping out in lots of areas, but in the future I want to establish my own applications.” It’s possible that the young scientist will embark on her own research project for this purpose, potentially in the area of quantum sensors, her self-confessed passion. But she may also go into industry directly. “Baden-Württemberg has a very lively start-up scene in the field of quantum technologies. That also interests me a lot.”

It goes without saying that at this stage of her scientific career, Luo is also contemplating the possibility of research in a third country. But this is not really a serious consideration for Luo Tingpeng at present. “Baden-Württemberg is very visible in the area of quantum technologies”, says the quantum researcher. “Maybe I have even more possibilities here than abroad.”

More information:

All those interested in the activities and opportunities at QuantumBW should get in touch with the office. (e-mail info@quantumbw.de) The office is run jointly by the Center for Integrated Quantum Science and Technology (IQST) at the University of Stuttgart and Ulm University together with Fraunhofer IAF and Fraunhofer IAO.

Tip for Researchers:

Can you imagine continuing your research career in Baden-Württemberg? Then, check our job engine!

Author: Andrea Mayer-Grenu, Translation: Tara Russell