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Calendar of Physics Talks Vienna
| Confining gauge theories on R3 X S1 with Higgs |
| Speaker: | Hiromishi Nishimura ((Universität Bielefeld)) |
| Abstract: | I will review some aspects of confining gauge theories on R3 X S1. Yang-Mills theory with certain center-stabilizing potentials is in the confined phase at small S1, and we can study confinement analytically using the semiclassical methods. Extending the theories with adjoint scalar fields, we show that there is a new type of confined phase and that the topological objects in this phase generalize BPS and KK monopoles, which are constituents of instantons. I will also argue how one may be able to take the theory at large R3 X S1 by the Poisson resummation. |
| Date: | Tue, 04.06.2013 |
| Time: | 12:30 |
| Duration: | 60 min |
| Location: | Vienna University of Technology (Freihaus Wiedner Hauptstasse 8-10 , 10th floor, Sem 136) |
| Contact: | stetina@hep.itp.tuwien.ac.at |
| "Der thermodynamische Limes in der Konstruktion Euklidischer Quantenfelder" |
| Speaker: | Jan Schlemmer (Mathematische Physik) |
| Abstract: | Am Ende der Konstruktion von wechselwirkenden Quantenfeldern im euklidischen
Rahmen muss man die Einschränkung der Theorie auf endliches Volumen wieder entfernen.
In diesem Vortrag soll es um den zweiten Teil einer Methode gehen, in der
dieser Limes unter Verwendung von Korrelationsungleichungen kontrolliert wird.
Für die Schwingerfunktionen der Theorie in endlichem Volumen werden
im Vortrag volumenunabhängige obere Schranken dargestellt, welche die Konvergenz
der Schwingerfunktionen im thermodynamischen Limes garantieren. Wichtigstes Werkzeuge
dabei ist ein Analogon zum Druck in der statistischen Mechanik; die oberen Schranken
folgen aus Abschätzungen dieses "Drucks".
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| Date: | Tue, 04.06.2013 |
| Time: | 14:15 |
| Location: | Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | J. Yngvason |
| There’s Life in the Old Dog Yet: New Insights from the Earth’s Oldest Known Magnetic Material (Fe3O4) |
| Speaker: | PhD Gareth Parkinson (Technische Universität Wien, Institut für Angewandte Physik) |
| Abstract: | Magnetite (Fe3O4), the material through which mankind first encountered magnetism, continues to fascinate scientists
with its remarkable properties. In this seminar I will present two very different recent highlights from our magnetite
project. Firstly, a combination of scanning tunneling microscopy (STM) and spin polarized low-energy electron
microscopy (SP-LEEM) sheds new light on how the (bulk) Verwey metal-insulator transition affects the Fe3O4(001)
surface. In the insulating low temperature phase a roof-like structure with a periodicity of ~0.5 μm emerges as a
consequence of micro-twinning within ferroelastic domains. The “Verwey roof”, as we call it, is visible as dark-light
stripes in SP-LEEM images, allowing the structural and magnetic domains to be studied in real-time.
In the second part of the talk I will show how gas molecules can induce atom mobility at surfaces. Specificall |
| Date: | Tue, 04.06.2013 |
| Time: | 16:00 |
| Location: | Technische Universität Wien, Institut für Angewandte Physik, Seminarraum 134A, Turm B (gelbe Leitfarbe), 5. OG, 1040 Wien, Wiedner Hauptstraße 8-10 |
| Contact: | Univ.Prof. Dr. Ulrike Diebold |
| Nanopatterning at the liquid/solid interface via molecular self-assembly: from fundamentals to applications |
| Speaker: | Prof. Steven De Feyter (Department of Chemistry, Division of Molecular Imaging and Photonics, Laboratory of Photochemistry and Spectroscopy, KU Leuven/Belgium) |
| Abstract: | Monolayers of molecules can be formed at a variety of interfaces, and over the years many techniques
have been developed to construct them and to study the resulting organisation of the molecules. At a
liquid-solid interface, 2D assemblies can be created by depositing a solution of the compound of interest
on top of the substrate. Depending on the nature of the solvent, the substrate, and the dissolved
molecules, the latter might form an ordered monolayer at the liquid-solid interface. When the interactions
remain relatively weak, the process is called physisorption. Advanced interface specific methods such as
scanning tunneling microscopy (STM) are needed to study the interface at the nanoscopic level.
We focus on several aspects of self-assembly at the liquid-solid interface, ranging from the fundamentals
to applications.
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| Date: | Wed, 05.06.2013 |
| Time: | 16:00 |
| Location: | Technische Universität Wien, Institut für Angewandte Physik, Seminarraum 134A, Turm B (gelbe Leitfarbe), 5. OG, 1040 Wien, Wiedner Hauptstraße 8-10 |
| Contact: | Univ.Prof. Dr. Ulrike Diebold |
| Searching for extra dimensions at the LHC |
| Speaker: | Lisa Edelhäuser (RWTH aachen university) |
| Abstract: | This talk gives an overview on models with universal extra dimen- sions. In these models, one has one or more compactified extra dimensions in which all particles can propagate. These models predict that each Standard Model particle is accompanied by a tower of Kaluza-Klein (KK) resonances which appear at a mass scale that is related to the radius R. Due to orbifolding of the ext- ra dimension, a so-called KK-parity remains, predicting a stable particle which can serve as a dark matter candidate. This sym- metry allows only pair production of the first KK modes, similar
to supersymmetry with R-parity.
However, canonical searches for the production and cascade decays of the first KK modes through missing transverse mo- mentum signatures suffer in general from low detection effici- encies because of the rather compressed KK particle mass spectrum. The talk will contain latest results on di |
| Date: | Wed, 05.06.2013 |
| Time: | 17:00 |
| Duration: | 60 min |
| Location: | Institute for High Energy Physics (HEPHY) 1050 Wien, Nikolsdorfer Gasse 18 Library, 1st Floor |
| Contact: | Ken Suzuki |
| Strong coupling from tau lepton decays |
| Speaker: | Matthias Jamin (Univ. Autonoma Barcelona) |
| Date: | Thu, 06.06.2013 |
| Time: | 14:15 |
| Location: | Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | ruth.bogoevski@univie.ac.at |
| Wealth and Social Behavior: Lessons from an Online World |
| Speaker: | Benedikt Fuchs (Med.Univ.Wien) |
| Abstract: | im Rahmen der gemeinsam veranstalteten Seminare "Komplexe Stochastische
Systeme" (Univ.Wien) und "Analyse Komplexer Systeme" (Med.Univ.Wien) |
| Date: | Fri, 07.06.2013 |
| Time: | 14:15 |
| Duration: | 90 min |
| Location: | Medizinische Universität Wien, Informatikbibliothek Bauteil 88, E 03, Spitalgasse 23 |
| Contact: | H. Hüffel, Stefan Thurner |
| Experimental realization of non-Abelian non-adiabatic geometric gates |
| Speaker: | Stefan FILIPP (ETH Zürich) |
| Abstract: | The evolution of a quantum system can result in a geometric phase which depends – in contrast to the dynamic phase – only on the path of the system’s state in Hilbert space. As a consequence, only fluctuations which distort the path contribute to geometric dephasing, if the system is subjected to noise. This noise-resilience of the geometric phase holds promise for robust quantum computation. In our experiments, we study geometric phases with superconducting artificial atoms (transmons) in the circuit quantum electrodynamics architecture. By adding artificial perturbations to the drive parameters, we have first verified the robustness of geometric phases with respect to noise that leaves the path unaffected [1]. We have then realized geometric single-qubit gates which are based on matrix-valued generalizations of geometric phases to degenerate quantum systems, so-called non-Abelian holonomies, and verified their non-commuting character [2]. When assisted by two-qubit gates, these operations may form the basis for a universal set of geometric quantum gates.
[1] S. Berger, M. Pechal, A.A. Abdumalikov, C. Eichler, L. Steffen, A. Fedorov, A. Wallraff, and S. Filipp. arXiv:1302.3305 (2013)
[2] A.A. Abdumalikov, J. M. Fink, K. Juliusson, M. Pechal, S. Berger, A. Wallraff, and S. Filipp. Nature 496, 482 (2013).
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| Date: | Fri, 07.06.2013 |
| Time: | 15:30 |
| Location: | TU Wien Atominstitut, Hörsaal, Stadionallee 2, 1020 Wien |
| Contact: | H. Rauch |
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