Hauptinhalt
Gemeinsames Kolloquium des
Fachbereichs Physik und des SFB 1083
Sommersemester 2023
mittwochs 15:30 Uhr
Renthof 5, Großer Hörsaal
26.04.2023 Christian Stegmann, DESY und Universität Potsdam
A New View of our Universe - Multimessenger Astronomy
Abstract:
On 17 August 2017, the measurement of a gravitational wave triggered an unprecedented astronomical observing campaign. More than seventy observers worldwide started observing the region of the sky from which the gravitational wave came. For the first time, the simultaneous measurement of gravitational waves and electromagnetic signals made it possible to track the merger of two neutron stars. The analyses following the discovery show the enormous scientific power of combining multi-messenger information. The measurement of the neutron star merger is just one of several examples that show the potential of the new multi-messenger astronomy.In September last year, the Federal Republic of Germany and the Free State of Saxony decided to establish the German Centre for Astrophysics in Lusatia as a result of the largest open science competition in Germany's history. An investment of this magnitude in basic science - that is remarkable. It shows not only the great fascination that astronomy and astrophysics hold, but also that they can provide important technological and innovative impulses in a very concrete way and enable sustainable structural change in Lusatia, a region in the centre of Europe.
What have we learned from measuring neutron star merger? What other examples of the new field of multi-messenger astronomy are there? And what role can the DZA play in this exciting field of research in the future? Christian Stegmann addresses these questions.
Christian Stegmann is Professor of Astroparticle Physics at the University of Potsdam, Director at the German Electron Synchrotron (DESY), Head of the DESY site in Zeuthen in Brandenburg and co-initiator of the German Centre for Astrophysics (DZA) in Lusatia.
03.05.2023 Christoph Freysoldt, MPI Düsseldorf
Exploring Data-Rich Materials Analytics with Machine Learning
Abstract:
The heart of modern material science lies in the dualism of experiments and a plethora of theoretical models to explain them. The on-going, rapid growth of available data and the rise of machine-learning and artificial intelligence offer novel ways for doing scientific research, but also challenge the traditional model-based understanding. Using examples from scanning transmission electron microscopy (STEM) and atom probe tomography (APT), I will show how data-centric methods can be turned into tools that both require and deliver scientific insight.17.05.2023 Marcus Rohleder, TenneT TSO
Energy Supply between Energy Security and Energy Transition
Abstract:
Our energy supply is currently undergoing a massive transformation, with "energy transition" and "energy security" being the driving factors. This presentation will look at the associated challenges from the point of view of the electricity transmission system operator, which as one of the main players in the background ensures that the electricity comes out of the socket today and will do so tomorrow.The electricity transmission system operator has a duty to ensure security of supply. In practice, this task spans operationally from the technical integration of renewable energies, the provision and expansion of the networks to the daily forecasting, monitoring and control of energy flows. Strategically, the TSO carries out calculations of future scenarios (e.g. in the grid stress test nuclear power) and develops market models to shape the European energy market design. In the lecture, these topics will be exemplified and deepened from a technical point of view, thus giving an insight into the exciting transformation of our energy landscape.
07.06.2023 Jürgen Janek, Universität Gießen
“Energy in the Box” – The Physical Chemistry of High-Performance Batteries
Abstract:
Electrochemical energy storage is a key technology in our “mobile society”, and is also expected to contribute to the future energy grid. Lithium ion batteries have evolved during the last 30 years as leading battery cell concept, and their further development drives world-wide research activities. In parallel and in view of the ever-increasing demand for the total storage capacity that amounts to hundreds or thousands of GWh, alternative electrochemical storage concepts based on compounds with virtually unlimited resources are also increasingly investigated. This lecture will therefore first focus on the (electro)chemical ingredients of state-of-the-art lithium ion batteries and their further evolution as reference for any alternative approach. Secondly, the lecture will try to consider electrochemical energy storage through the eyes of a physicochemist who knows well the different views of physicists and chemists.21.06.2023 Bart Verberck, Editor at Nature Physics
Publishing in Nature Physics
Abstract:
After a brief introduction to Springer Nature and the Nature Portfolio — the brand behind the ‘Nature journals’ — I will provide an overview of the inner workings of a Nature research journal, with Nature Physics as an example. I will focus on the editorial process at a Nature research journal, explain the roles of editors and discuss editorial criteria for publication. Along the way, I will give some advice on how to present research. I will reflect on the value Nature Physics aims to bring to the physics community, as well as on the ever-evolving role of scientific publishers and, particularly, on the ongoing transition to fully open access publishing.28.06.2023 Witlef Wieczorek, Chalmers University of Technology
Towards Quantum Experiments with Micrometer-Sized Particles
Abstract:
Quantum states of massive objects have fascinated since the inception of quantum mechanics. Nowadays molecules of thousands of atoms and nanomechanical resonators weighing picograms can be brought into quantum states. This capability enables tests of the validity of quantum mechanics and provides new avenues for quantum technologies. To explore even more massive quantum systems requires exceptional isolation of the system from the environment and precise control over its quantum state. I will present first steps in the development of a new experimental platform that may allow quantum control over the motion of objects with masses larger than 10^13 atomic mass units. This platform is based on magnetically levitating a superconducting microparticle in cryogenic vacuum05.07.2023 Hagen Klauk, MPI Stuttgart
Flexible Nanoscale Organic Thin-Film Transistors
Abstract:
Organic thin-film transistors (TFTs) are field-effect transistors in which the semiconductor is a thin layer of conjugated organic molecules. Unlike transistors based on inorganic semiconductors (such as silicon or zinc oxide), organic TFTs can often be fabricated at process temperatures no higher than about 100 degrees Celsius and thus on a wide range of unconventional substrates, including plastics, textiles and paper. This makes organic TFTs potentially useful for flexible electronics applications, such as foldable or rollable displays or conformable sensor arrays. An important performance parameter of transistors in general (and of organic TFTs in particular) is the transit frequency, which is the highest frequency at which the transistors are able to switch or amplify electrical signals. A field-effect transistor’s transit frequency depends critically on the channel length and the parasitic gate-to-contact overlaps. Since organic TFTs often have channel lengths and overlaps of several microns or even tens of microns, their transit frequencies are usually no higher than a few megahertz. To explore the performance of organic TFTs with aggressively scaled dimensions, we have used electron-beam lithography and fabricated organic TFTs with channel lengths and overlaps as small as 100 nm on flexible plastic substrates.12.07.2023 Gunter Erfurt, Meyer Burger
Solarindustrie 2.0 in Europa - Zurück zu den Wurzeln einer Einstein'schen Schlüsseltechnologie