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Calendar of Physics Talks Vienna
| * 23.07.2019 {{:seminars:2019-07-23_egdell.pdf|Russell G. Egdell: Systematic trends in electronic structure in complex lanthanide oxides}} |
| Speaker: | Laerte Patera (University of Regensburg, Institute of Experimental and Applied Physics, Regensburg/Germany) |
| Abstract: | Electron transfer plays a crucial role in many chemical processes, from photosynthesis to combustion and corrosion. However, the way in which redox reactions affect individual molecules and, in particular, their electronic structure, remains largely unclear. Unveiling these fundamental aspects requires the development of experimental tools allowing the observation of electron transfer down to the single molecule level. Here, we demonstrate the capability of performing tunnelling experiments on non-conductive substrates to map the orbital structure of isolated molecules upon electron transfer. By driving a change in the redox state of a molecule synchronized with the oscillating tip of an Atomic Force Microscope, previously inaccessible electronic transitions are resolved in space and energy [1].
Our results unveil the effects of electron transfer and polaron formation on the single-orbi |
| Date: | Tue, 03.09.2019 |
| Time: | 16:00 |
| Location: | TU Wien, Institut für Angewandte Physik, E134 1040 Wien, Wiedner Hauptstraße 8-10 Yellow Tower „B“, 5th floor, SEM.R. DB gelb 05 B |
| Contact: | Univ.Prof. Dr. Ulrike Diebold |
| Parity anomaly in even dimensions |
| Speaker: | Dmitri Vassilevich (ABC Federal U.) |
| Abstract: | It is known for a long time that Dirac fermions in odd dimensions have a parity anomaly. I will show that the parity anomaly exists also in even dimensions and is given by a boundary term. This anomaly is given by a Chern-Simons type action having a surprising level k=1/4. I will explain why this result is actually natural and discuss some physical implications. |
| Date: | Thu, 05.09.2019 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Inst. f. Th. Phys. TU Wien, seminar room 10th floor, Wiedner Hauptstrasse 8-10 |
| Contact: | Daniel Grumiller |
| Properties of dyons in N=4 theories at small charges |
| Speaker: | Justin David (IISc, Bangalore) |
| Abstract: | The discovery of Mathieu moonshine in the elliptic genus of K3 allows the construction of twisted ellipitc genera to every conjugacy class of the Mathieu group M23. These twisted elliptic genera play an important role in both N=2 and N=4 string compactifictions. In N=4 compactifications they are inputs to degeneracies of 1/4 BPS dyons, which at large values of charges are black holes. We study properties of these states at small values of charges which provide insight to their geometric description as black holes. |
| Date: | Thu, 05.09.2019 |
| Time: | 16:00 |
| Duration: | 60 min |
| Location: | Institute for Theoretical Physics, TU Wien, Seminar room 10th floor (yellow area), Wiedner Haupstr. 8-10, 1040 |
| Contact: | Timm Wrase |
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