29.10.2026          Antrittsvorlesungen | Dr. Imbrock, Dr. Laumann, PD Dr. Mönig

Vortragsankündigung(en) [PDF]

Light-Structured Photonics: From Nonlinear Beam Shaping to Optofluidics

PD Dr. Jörg Imbrock, Institut für Angewandte Physik

How can light be used to structure matter, and how can these structures, in turn, control light and microscopic objects? These questions provide a starting point for exploring the physical principles of light-induced material structuring and their applications in nonlinear optics and optoelectronics.

Ferroelectric crystals, particularly lithium niobate, provide a versatile platform for studying these interactions due to their nonlinear optical, pyroelectric, and photovoltaic properties. Starting from the fundamentals of second-harmonic generation, we will explore how spatial modulation of the second-order nonlinear susceptibility enables quasi-phase matching and the shaping of newly generated optical fields. Different approaches to modifying the quadratic nonlinearity will be introduced, including femtosecond laser writing and light-assisted ferroelectric domain inversion, while second-harmonic generation microscopy provides a means to visualize the resulting structures.

Beyond nonlinear optics, light-induced photovoltaic charge distributions can generate spatially structured electric fields that act as virtual electrodes. These fields enable the controlled manipulation of particles and liquid droplets, opening possibilities for optofluidic applications.

Together, these examples illustrate how light can be used to engineer nonlinear optical structures and spatially controlled electric fields, enabling the manipulation of both optical waves and microscopic objects. The interplay between optical, electrical, and ferroelectric properties provides a common framework connecting nonlinear photonics with optoelectronic applications.

Interest and instruction: Two sides of learning physics

PD Dr. Daniel Laumann, Institut für Didaktik der Physik und Physikalisches Institut

Imagine two students encountering the same physics topic. One is fascinated and keeps asking questions, the other sees little point. Now imagine the topic is taught in two different ways: as a carefully designed animation with narration, or as a real experiment supplemented by digital visualizations. The same two students may react very differently to each version. Teaching physics pursues two goals at once: Building subject-specific competencies and fostering interest in physics. The latter is a goal in its own right, but also a prerequisite for the former, since interested learners engage more deeply and persistently. Both goals depend on who is learning and on how instruction is designed.

Who is interested in physics, and why? Drawing on Krapp’s person–object theory of interest, I will show that research has focused almost exclusively on gender, although interventions aimed at girls have shown only modest success. I will present studies on the importance of systemizing thinking and further personal characteristics as predictors of students’ interest.

Interest alone does not produce knowledge, however. The second perspective therefore turns to the design of (digital) media, grounded in the cognitive theory of multimedia learning. Its principles were established mainly for seeing and hearing, although other modalities are central to physics. I will show how we extended the theory, tested whether its principles hold beyond these two channels, and why complexity turns out to be a decisive boundary condition.

This suggests a broader lesson: To understand and promote learning in physics, we need to look beyond simple group differences, at the individual learner and the learning environment alike.

Dynamic Force Microscopy with Atomically Defined Probe Tips

PD Dr. Harry Mönig, Physikalisches Institut

The implementation of atomically defined probe tips in non-contact atomic force microscopy (nc-AFM) not only provides increased resolution and reproducibility, but also enables precise control over chemical interactions. In conjunction with ultra-sensitive qPlus force sensors, this allows imaging organic nano-structures with sub-molecular resolution, which has led to a new era in surface chemistry. Highlighting their potential for elemental and chemical discrimination, presented examples include the use of oxygen-terminated copper tips in imaging the sublattices and defect structures of heterogeneous surfaces. Beyond imaging, the atomic-scale control of probe tips allows for tailored force spectroscopy and tip manipulation experiments with picometer and piconewton resolution. Controlling nc-AFM probe tips on an atomic level constitutes a powerful opportunity to standardize such experiments, which greatly improves the fundamental understanding of surfaces and interfaces toward applications ranging from heterogeneous catalysis to electronics, and energy conversion where the local atomic structure largely determines the performance of the material systems and devices.

19.11.2026          CRC 1459 Colloquium | Prof. Danqing Liu & Prof. Karen Alim

Abstract Book CRC 1459 Colloquium 2026 [PDF]

> Designing Interactive Liquid Crystal Polymers for Haptics and Soft Robotics (Liu) &

> Learning without a Brain (Alim)

CRC 1459 Intelligent Matter | Events

26.11.2026          Dr. Joachim Deisenhofer (Universität Augsburg)

Vortragsankündigung [PDF]

Morphic effects - phonon selection rules and magnetic order

A The selection rules of optical phonons in a non-magnetic or paramagnetic solid are determined by the irreducible representations of the crystallographic point group. When the material orders magnetically, only those symmetry elements of the paramagnetic state, that will also leave the ordered spin configurations invariant, remain valid for the magnetic crystal and form the magnetic point group. The irreducible representations of the magnetic point group - the irreducible corepresentations - can now give rise to new selection rules and previously silent modes can become active of IR and Raman active phonon modes can occur in previously forbidden channels. These effects have been known and described several decades ago [1, 2], but only few examples of morphic effects of phonons have been reported in the past.

I will discuss our investigations of such morphic effects of phonons with regard to the collinear magnets Co2Mo3O8, Fe2Mo3O8, and Mn2Mo3O8 [3, 4], all of which break the combined PT-symmetry operation of spatial inversion P and time inversion T. Hence, Kramers degeneracy is lifted and spin-splitting of electronic or magnon bands at general points in the Brillouin zone can occur. Moreover, I will discuss the behavior of phonons and magnons of these compounds in magnetic fields, where strong magnon-phonon hybridization and Faraday effects have been observed.

[1] E. Anastassakis and E. Burstein, Morphic effects. V. Time reversal symmetry and the mode properties of long wavelength optical phonons, Journal of Physics C: Solid State Physics 5, 2468 (1972).

[2] C. J. Bradley and A. P. Cracknell, The Mathematical Theory Of Symmetry In Solids: Representation theory for point groups and space groups (Oxford University PressOxford, 2009).

[3] F. Schilberth, M. Kondákor, D. Ukolov, A. Pawbake, K. Vasin, O. Ercem, L. Prodan, V. Tsurkan, A. A. Tsirlin, C. Faugeras, P. Lemmens, K. Penc, I. Kézsmárki, S. Bordács, and J. Deisenhofer, Optical phonons as a testing ground for spin group symmetries, npj Quantum Materials 11, 26 (2026).

[4] F. Schilberth, K. Vasin, M. Knauft, M. Kondákor, M. Vuckovic, N. Herrmann, K. Penc, M. Minola, B. Keimer, V. A. Martinez, K. Panda, A. A. Sirenko, L. Prodan, V. Tsurkan, A. A. Tsirlin, I. Kézsmárki, and J. Deisenhofer, Magnetic circular dichroism of THz modes and selection rules of Raman-active optical phonons in the polar altermagnet candidate Mn2Mo3O8 10.48550/arXiv.2608.01062 (2026), arXiv:2608.01062.

03.12.2026          Prof. Matthias Kleinmann & Prof. Adrian van Kan

Lecture announcement [PDF]

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• Prof. Dr. Matthias Kleinmann (Department for Quantum Technology)
• Prof. Dr. Adrian van Kan (Geodynamics Group)

17.12.2026          N.N.

Vortragsankündigung [PDF]

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07.01.2027          N.N.

Vortragsankündigung [PDF]

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14.01.2027          Prof. Ian D. Sharp (Exp. Halbleiterphysik, TU München)

Vortragsankündigung [PDF]

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21.01.2027          Prof. Stephan Götzinger (MPI für Physik des Lichts, Erlangen)

Vortragsankündigung [PDF]

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28.01.2027          Antrittsvorlesungen | Moreira de Godoy Willems, Raissi, Stemer

Vortragsankündigung(en) [PDF]

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• Jun.-Prof. Dr. Denise Moreira de Godoy Willems (Institut für Kernphysik)
• Jun.-Prof. Dr. Zahra Raissi (Department für Quantentechnologie)
• Jun.-Prof. Dr. Dominik Stemer (Physikalisches Institut)

Jun.-Prof. Dr. Dominik Stemer, Physikalisches Institut

Life as we know it is crucially dependent on water. Biochemistry occurs nearly exclusively in aqueous environments, either under bulk solvation conditions or at aqueous interfaces. Beyond simply acting as the ubiquitous medium within which important biochemical reactions occur, water also plays a critical active role in determining the functionality of biomolecules such as amino acids, proteins, and DNA via structure stabilization and mediation of intra- and intermolecular interactions. These building blocks of life are predominantly chiral, meaning that they have a defined handedness and are non-superposible with their mirror images. Although generally chemically and physically indistinguishable, the mirror-image enantiomers of chiral molecules interact differently with other chiral entities. As a result, the activity of these enantiomers can differ dramatically under biological (chiral) conditions. Intermolecular interactions between chiral solutes and neighboring water molecules may also induce chirality in the solute’s hydration shell, with profound implications for enantiomer-dependent chemistry in solution. A clearer understanding of molecular chirality in aqueous solution is thus directly relevant for chemical and life sciences.

In this talk, I will outline my plans to develop a novel and powerful technique to explore chirality in aqueous solutions of amino acids: enantiosensitive liquid-jet photoelectron spectroscopy (LJ-PES). Standard LJ-PES enables the direct study of occupied electronic states for volatile solvents and solutions with site- and chemical-state specificity. I will extend this technique by leveraging two recently-identified phenomena that highlight the photoelectron’s capacity to directly access molecular chirality: photoelectron circular dichroism (PECD) and chirality induced spin selectivity (CISS). Briefly, the former effect describes the asymmetry in the angular distribution and the latter in the spin polarization of photoelectrons generated upon photoionization of chiral systems under specific experimental conditions. Recent technical developments have made possible the investigation of these effects for aqueous solutions.

04.02.2027          N.N. (Einladender: Prof. Donath)

Vortragsankündigung [PDF]

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