Joint research group for quantum computing and simulation
© Freie Universität Berlin
Freie Universität Berlin and Helmholtz-Zentrum Berlin (HZB) are now strengthening their cooperation in the field of quantum computing with a new research group. Quantum materials exhibit very interesting properties, which researchers want to use to make data processing significantly faster and more efficient than is currently possible. They can study these materials excellently at synchrotron radiation sources such as BESSY II. It has proven especially promising to predict the material properties in quantum simulations before running the experiments. Taking this approach allows such experiments to be conducted more targetedly.
“Simulating how highly complex material properties emerge”
Jens Eisert is a professor of physics at Freie Universität Berlin and the head of the joint research group. He is an internationally renowned expert for quantum many-body theory, quantum information theory, and quantum optics.
How did this collaboration with HZB come about?
Jens Eisert: Our collaboration arose out of promising and inspiring discussions with Bella Lake, a physicist at Helmholtz-Zentrum Berlin. We had been working on problems of strongly correlated systems in the laboratory, which were difficult to solve with conventional methods. At that stage, the methods of tensor networks were able to deliver the first insights for those systems, but not a comprehensive picture. It took a lot of hard work before we could develop methods powerful enough to model and simulate correlated systems out of the laboratory. From this cooperation, we recognised the major potential that existed in stronger collaboration.
What other points of contact do you see between your research and the topics addressed at HZB?
There are many opportunities. The initial discussions with Bella Lake have culminated in a research programme that offers many possibilities – a genuinely comprehensive programme.To name a few, Johannes Reuther, Oliver Rader, Boris Naydenov, Annika Bande, and other researchers from HZB have announced their interest in collaborating. And indeed it makes sense, from a strategic point of view, to build up a combined initiative on quantum technologies in Berlin.
Are there already any concrete ideas for practical projects the research group can work on?
Definitely. There are many topics that we are already working on, or intend to tackle soon. As a concrete example, we are investigating how highly complex properties emerge out of simple interactions in quantum materials – and how they can be modelled. Together, we also want to delve deeper into questions of realistic quantum computers and quantum simulators. First, we will recruit two new researchers to tackle those questions. They will be working mainly at Freie Universität Berlin, but will maintain very close contact with HZB. I am very pleased about this collaboration because working directly with groups from HZB who also conduct experiments is very fruitful for theoretical physics.
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- Solar cells on moon glass for a future base on the moonFuture settlements on the moon will need energy, which could be supplied by photovoltaics. However, launching material into space is expensive – transporting one kilogram to the moon costs one million euros. But there are also resources on the moon that can be used. A research team led by Dr. Felix Lang of the University of Potsdam and Dr. Stefan Linke of the Technical University of Berlin have now produced the required glass from ‘moon dust’ (regolith) and coated it with perovskite. This could save up to 99 percent of the weight needed to produce PV modules on the moon. The team tested the radiation tolerance of the solar cells at the proton accelerator of the HZB.