Quantum leaps in the heart of the city

In three science tents in Erlangen’s city center, researchers from Erlangen and the Zukunftsmuseum Nürnberg presented six experiments and four exciting short lectures. Among other things, the team led by MPL Director Prof. Vahid Sandoghdar demonstrated nano-optical methods with which they are constantly pushing the limits of resolution. Visitors were able to observe individual dye molecules measuring 10^-6 millimeters, live. In the experimental setup of the ›Fiber Production & Glass Studio‹ technology unit, Dr. Michael Frosz made “photons dance.” Stimulated by ultraviolet light, quantum transitions appear in a special lead glass. The metal Europium in the glass absorbs the UV light, causing the Europium atoms to transition to an excited energy state. When they fall back to their ground state, they emit photons with lower energy, causing the glass to glow bright red. 

›A single ion you can touch‹ was the promise of the experiment conducted by the emeritus group of MPL founding director Gerd Leuchs. Visitors were able to follow live on a monitor how a single ion was captured and controlled in a trap. The ion was cooled to a temperature of approximately -273.149 °C. Visitors were also able to observe individual quantum leaps – a fascinating insight into a world that is normally inaccessible to the naked eye.

Big research at lunchtime – easily digestible in small bites

In short “Science-to-go” talks, researchers presented their current projects in the field of quantum research. Whether it was quantum encryption, microresonators, optical clocks, or the coupling of light and sound waves, the 15-minute presentations showed that modern technologies are based on the principles of quantum mechanics. They also highlighted how active and diverse research in this field is.

MPL research group leader Christoph Marquardt, who is also a professor at Friedrich-Alexander-Universität Erlangen-Nürnberg, reported on a recent experiment in which individual photons were sent from a research aircraft circling above MPL to an ion trap in the laboratory. The goal: to test fundamental technologies for stable and secure quantum communication under realistic conditions. The next speaker, MPL Director and Head of the Theory Division Prof. Florian Marquardt, explained the importance of quantum physics to the further development of artificial intelligence and neural networks. In the following presentation, MPL research group leader Dr. Pascal Del’Haye explained how light can be captured using micro-resonators and how these are manufactured. His research team is also working on optical clocks which are even more accurate than atomic clocks – a topic he also highlighted to the Erlangen audience. Equipped with a ukulele, MPL research group leader in Quantum Optoacoustics Birgit Stiller, who also holds a professorship at Leibniz University Hannover, began her presentation. Not only was the musical introduction unexpected, but her field of science is also surprising in that it combines two different disciplines – optics and acoustics. She studies the interaction between the completely different types of waves, light and sound – a promising field of research for data processing, secure quantum communication, and the storage of light information.

A peek behind the scenes of cutting-edge research

In the early evening, the event moved to the MPL campus. There, guests were treated to a varied program of lectures, lab tours, and a film. Prof. Florian Marquardt covered a century of quantum science. In his lecture, he talked about the birth of quantum mechanics in the summer of 1925 on Heligoland, which laid the foundation for today’s quantum science. These findings form the basis for quantum computers, for example. Due to their complexity, they are still highly susceptible to errors. Prof. Marquardt explained, among other things, how artificial intelligence can help to correct these errors. Prof. Birgit Stiller then provided an insight into the world of quantum optoacoustics. For example, information from light pulses can be transmitted in sound waves. In this way, sound can act as a kind of temporary storage medium for information. This knowledge benefits research into quantum computers and communication, among other things.

During the laboratory tours, visitors were able to marvel at wafer-thin photonic crystal fibers, ultra-fine etching, and complex laser setups. The laboratories of the ›Quantum Optoacoustics‹ group and the two technology and service units ›Micro- and Nanostructuring‹ and ›Fiber Fabrication & Glass Studio‹ provided rare insights into the working environment of the researchers. The day concluded with a screening of the documentary film ›Tracing Light‹, which impressively illuminates the phenomenon of light from a scientific and artistic perspective – with scenes shot at MPL, among other locations.

The joint event was a successful gathering and interaction between researchers, museum educators, and interested people of all ages and backgrounds. The day impressively demonstrated how complex science can be communicated in a lively way – and how direct exchange with the public can spark enthusiasm for research.