by Janina Balzer

Already in the lecture hall at 13? No problem for Jonathan Bork (video here). Alongside school, he is taking part in the UDE's early studies program, writing exams in physics and examining silicon wafers. In this interview, he explains how he manages to juggle everything.   

Jonathan, you're in year 10 and attending university - were you looking for more of a challenge?
You could say that! I've always been fascinated by physics - I find science in general really exciting and I just wanted more. I found out about early studies by chance and thought to myself: why not? So I signed up for a lecture in the winter semester 2024/2025, did an internship in a research group, and I enjoyed it so much that I decided to stick with it.

What excites you about early studies?
It's great to deepen your knowledge of a subject as a pupil. You get an insight into university life, can gain initial experience and find out whether studying in this field is really the right thing for you. I can only say: definitely try it out!

What are you doing exactly?
I attend lectures and tutorials on the basics of physics to expand my knowledge. In parallel, I'm in Professor Martin Mittendorff's working group. It's all about terahertz spectroscopy. Put simply, it's about radiation that lies between the microwave and infrared range. We use it to find out more about material properties - for example, to say how well a material transmits or reflects radiation. I will also have my own project in which I am investigating the reflective capabilities of silicon wafers. These are very thin slices of high-purity silicon that are used in the semiconductor industry. They are important for the production of microchips or solar cells.

Doesn't that make school boring?
The early studies and the research group actually help me at school too. I see everything from a completely different perspective. Especially in math. There's a lot of math in physics and my understanding of it has improved a lot thanks to my studies.

How do you manage to juggle everything - school and studies?
My school gives me time off for early studies. And the workload is manageable - with the right organization, it works quite well. I also like the system at the university: there is a clear separation between lectures and tutorials, which makes learning much easier. Of course, the first lecture was still exciting.

Is there still time for leisure?
University is like homework for me. After that, I still have time for other things: I like to play Minecraft, meet up with friends or visit the horses at my parents' stables. I'm also involved in hybrid education concepts - it's a project close to my heart.

What is hybrid education?
It's about combining face-to-face teaching with flexible self-learning phases. This allows students to learn from home or at school, depending on their needs. This is particularly helpful for highly gifted or neurodivergent children with ADHD or autism, for example, whose brains function differently to the neurotypical standard. And I talk to politicians about this or present the concept at education festivals. My concept is already being used in some federal states, for example at vocational schools in North Rhine-Westphalia or at project schools on hybrid education in Berlin. Schleswig-Holstein is currently trying to implement the concept in mainstream schools.

I have already spoken to education experts all over the world, for example I am in contact with the OECD Director of Education - hybrid education is a very favorable and effective option here. It is therefore important that more federal states adopt these approaches and that the education system becomes more modern and inclusive in the long term.

What are your goals?
First of all, to do my Abitur. After that, I definitely want to study physics. In the long term, I could imagine staying in research. My commitment to hybrid education is also important to me. I want to develop the concept further and get schools and politicians to allow more flexible learning models. It would be great if more pupils could learn individually and in a self-determined way - just as is possible with early learning.

Janina Balzer asked the questions.

In the picture:
Jonathan Bork in the physics lab

Sen. Prof. Dr. Dietrich Wolf from our faculty was received with great interest when he visited the Gesamtschule Horst as part of the Energy Science project course to give a lecture on the topic of ‘Energy Science’ and to present our degree programme of the same name. The following article is taken from the school's homepage:

‘Pupils from Gesamtschule Horst were given the opportunity to engage in a direct and practical exchange with a renowned scientist from the University of Duisburg-Essen in the subject of physics. Prof. Dr Dietrich Wolf, an internationally recognised physicist and energy researcher, inspired the pupils with well-founded scientific insights.

In close co-operation, a teaching concept was developed that sheds light on central topics of modern energy science: Forms of energy, mechanical energy conversion, renewable energies, the greenhouse effect and global energy requirements. In five practice-orientated workshops, complex concepts were conveyed and made tangible through interactive and experimental elements.

The pupils were given exclusive insights into current research and university study programmes. The opportunity to discuss at the highest academic level broadened their professional horizons and strengthened their scientific mindset and study orientation in the long term.

It is a special honour that a scientist of such renown invests his time to support young talent. We look forward to further intensifying this exchange in the future.

Ann-Sophie is a PhD student in Marika Schleberger's group at the University of Duisburg-Essen. She received her Master of Education in mathematics and physics with the goal of becoming a teacher. However, after completing her degree, she decided to embark on a research career and her doctorate in physics. As part of the CRC 1242, her research focuses on ultrafast non-equilibrium dynamics in condensed matter, particularly through time-resolved ion-induced photoelectron emission spectroscopy.

Simulations predict that the interaction and relaxation processes within the electronic and phononic systems following an ion impact occur on timescales ranging from sub-picoseconds to nanoseconds. Experimentally verifying these dynamics, however, poses a real challenge due to the precision required to pinpoint the ion impact in time and the creation of a suitable (sub-)picosecond ion pulse. Within the framework of Project C05 of the CRC 1242, such a source has been developed, enabling the creation of picosecond ion pulses via femtosecond photoionization of noble gas atoms.

Building on this achievement, Ann-Sophie is conducting the world ́s first pump-probe experiment using ions as a pump source. Her work investigates ion-induced non-equilibrium dynamics in solids, providing unprecedented experimental insights into these processes. This research represents a groundbreaking step in understanding the fundamental ultrafast dynamics triggered by ion impacts.

by Birte Vierjahn 03.02.2025

A team led by physicists from the University of Duisburg-Essen has succeeded for the first time in precisely determining the spin texture of previously generated merons and drawing conclusions about the topological properties of these structures. Their findings, published in Advanced Photonics, could help to transmit and store information more securely in the future.

Electrons that move collectively in a noble metal are known as plasmons. They are used in catalysis and sensor technology, for example. Laser pulses lasting a few femtoseconds are used to investigate the wave-like propagation of plasmons on precious metal surfaces with a time resolution. A femtosecond corresponds to a millionth of a billionth of a second. With a time resolution that is 10 times better, the movement of plasmon waves can be imaged in a photoelectron microscope at almost the speed of light in space and time. The working group led by Prof Dr Frank-J. Meyer zu Heringdorf from the Department of Physics at the University of Duisburg-Essen (UDE) has been developing this type of time-resolved microscopy for many years. Their work has attracted worldwide attention.

Now the UDE team, together with colleagues from the Universities of Stuttgart and Melbourne (Australia), has achieved something unique: They have measured the electric field structure of plasmon waves with unprecedented temporal and spatial precision to such an extent that the topological properties can be derived from them. ‘Topology is a mathematical theory in which different objects can actually be classified on the basis of superordinate geometric properties,’ says Meyer zu Heringdorf. ‘The best-known example is probably the topological equality of a cup with a handle and a doughnut: both are different objects, but both have exactly one hole.’

The scientists have now investigated the local spin texture of a so-called meron pair. Merons are topologically stable structures in which spin vectors are arranged in a certain way. ‘If you transfer the spin vectors to a sphere (like cheese sticks to a melon) and only one half of the sphere is covered by vectors, the topology corresponds to that of a meron,’ explains the physicist. A meron pair consists of two identical merons. ‘For our experiments, we used ultrashort laser pulses to measure the electric fields. We were then able to derive the magnetic fields from the measured data and calculate the spin moment on this basis.’

The research team was thus able to prove that the topology of the plasmon is constant, even though the electric and magnetic fields oscillate and rotate with a period of 2.66 femtoseconds. This stability could help to securely store or transmit information in the future, as topological light in glass fibres would be more resistant to losses and interference.

In the picture:
Spin texture of a meron pair. The measured spin vectors are shown on a gold surface. If the arrows were placed on a sphere, they would cover the same (northern) hemisphere twice, while the southern hemisphere would remain uncovered.

Crystals are highly symmetrical, but quasicrystals lack important symmetry properties. These solids pose a puzzle for physics. A research team from the Technion in Haifa, the University of Duisburg-Essen and the University of Stuttgart has now solved one of them. They discovered that the symmetry is hidden in a higher spatial dimension.

When analysing collective electron oscillations (plasmons) on gold surfaces, the scientists discovered a quasi-crystalline pattern. Inspired by earlier plasmon experiments, they searched for the missing symmetry - and found it in four-dimensional space. This required time-resolved microscopy experiments on a millionth of a billionth of a second scale - a speciality of the team led by Prof. Frank Meyer zu Heringdorf from UDE's Department of Physics. The international research group has now published the results in the renowned journal Science.

In the picture:
Low-energy electron microscope of Prof Frank Meyer zu Heringdorf's research group.

The Board of Directors of the Center for Nanointegration Duisburg-Essen (CENIDE) has elected Prof. Dr Sebastian Schlücker from the Faculty of Chemistry as the new Scientific Director and Prof. Dr Marika Schleberger from our Faculty of Physics as Deputy Scientific Director.  Prof Dr Heiko Wende, also from the Faculty of Physics, is stepping down from the position of Scientific Director after six years.
CENIDE is an interdisciplinary network at the University of Duisburg-Essen consisting of 79 professors and working group leaders - 24 of them from the Faculty of Physics alone - which promotes ‘interdisciplinary cooperation and helps to bridge the gap between basic academic research and industrial implementation’.

Planets are formed when dust and rock in a disk around a young star collide and combine to form ever larger bodies. This so-called accretion is not yet fully understood. Astrophysicists at the University of Duisburg-Essen were able to make significant observations of collision speed and electrical charge of the particles through experiments on a suborbital flight. Their results have just been published in Nature Astronomy*.

The direct connection between two places as the crow flies is generally shorter than the distance you have to travel by car. Two physics research groups at the University of Duisburg-Essen have now discovered this: The distance between two locations in a highway network is typically 1.3 times longer than their connection as the crow flies. Their genuinely new finding is based on an extensive analysis of data from Europe, Asia and North America and was published in the journal npj Complexity.

The study was carried out by the Statistical Physics of Complex Systems working group led by Prof. Thomas Guhr and the Physics of Transport and Traffic working group led by Prof. Michael Schreckenberg. They determined the distance between around 2,000 locations within France, Germany, Spain, China and the USA. To do this, they used freely available geodata and compared the distance over the highway network with the respective geodetic distance - the direct connection between two places, as a bird could fly. They found that the ratio of the two distances is quite universal: the distance by car is usually 1.3 (± 0.1) times longer than as the crow flies.

“This stable relationship across countries and continents is the result of two competing societal needs,” explain the study leaders. “On the one hand, we want to get to our destination quickly and efficiently, and on the other, we want to keep costs and environmental impact as low as possible.”

From their findings, a new model for planning highway networks was derived, which they call a “partially random highway network”. It is based on the idea of making efficient use of existing links by connecting neighboring regions in stages. The random part of the model consists of making certain connections between cities and towns in the highway network only with a certain probability. Defined rules ensure logical connections and good networking.

In future, the model could improve the efficiency of transportation routes and at the same time reduce their environmental impact.

Original publication: https://doi.org/10.1038/s44260-024-00023-x

Further information:
Prof. Dr. Thomas Guhr, Statistical Physics of Complex Systems, Tel. 0203/379-4730, thomas.guhr@uni-due.de
Prof. Dr. Michael Schreckenberg, Physics of Transport and Traffic, Tel. 0203/379-3552, michael.schreckenberg@uni-due.de

Editor: Birte Vierjahn, Tel. 0203/37 9-2427, birte.vierjahn@uni-due.de

An important decision will soon have to be made for all those finishing school this year: the decision for or against a course of study and the choice of degree program.

The Faculty of Physics at the University of Duisburg-Essen is happy to provide support and information. We will present our Energy Science, Physics and Physics Teacher Training degree programs via video conference on the following dates

• Saturday, February 1st 2025, 1-2 p.m.
• Tuesday, March 18th 2025, 5-6 p.m.
• Monday, Marchg 24th 2025, 5-6 p.m.

Afterwards, questions can be asked in a relaxed round. Contact persons are at least two students and one full-time lecturer. The students are part of our buddy system. Within the Buddy System, we offer all-round advice for future students before the start of their studies and during the first two semesters. Further information on the Buddy System can be found on the Buddy System homepage and in the flyer.

If you would like to take advantage of this offer (buddy@school digital 2025), please register simply and briefly (at least one week before the desired date) via the online form at https://udue.de/bas25. The offer is of course also available to those who will not be finishing school until the next few years but would like to find out more today.

We look forward to seeing you!