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Calendar of Physics Talks Vienna
| Terahertz Radiation-Induced Electric Currents in Dirac Fermions Systems |
| Speaker: | Prof. Sergey D. Ganichev (University of Regensburg) |
| Abstract: | The talk overviews experimental and theoretical studies of photocurrents induced in various Dirac fermions systems by polarized electromagnetic radiation. We consider second order opto-electric phenomena induced by terahertz radiation in graphene and in HgTe/CdHgTe quantum wells. We discuss the phenomenological and microscopic theory of these phenomena and present the state-of-the-art of the experiments aimed to the study of terahertz radiation induced non-linear electron transport. We also show that nonlinear transport opens up new opportunities for probing of Dirac electrons as well as address prospective of future theoretical and experimental studies. |
| Date: | Tue, 26.11.2013 |
| Time: | 11:00 |
| Duration: | 45 min |
| Location: | TU Freihaus, seminar Room 138C, yellow tower, 9’th floor |
| Contact: | Andrei Pimenov |
| Hard Particles in Theory, Simulation and Experiment |
| Speaker: | Carina Karner (University of Vienna) |
| Abstract: | In the 1950's, when computational methods were established as new way to study and understand physical phenomena, hard spheres were among the first systems studied. As early as 1957 Alder and Wainwright showed that hard spheres exhibit a first order ordering phase transition. Now, 50 years later, hard spheres and their experimental realizations, colloidal particles with nearly hard interactions are still a very attractive object of research. Nowadays, new real-space imagining techniques enable the experimental study of nucleation of hard colloidal spheres and, by that, testing theoretical findings and numerical results. Besides hard colloidal spheres, experimentalists can now, due to the advent of new fabrication techniques, produce colloidal particles with various shapes or interactions. |
| Date: | Tue, 26.11.2013 |
| Time: | 12:30 |
| Duration: | 60 min |
| Location: | Vienna University of Technology, Wiedner Hauptstr. 8-10, yellow area, 10th floor, seminar room E136 |
| Contact: | Iva Lovrekovic, Albert Georg Passegger - www.univie.ac.at/lunch-seminar |
| Asymptotic properties of von Neumann algebras |
| Speaker: | Hiroshi Ando (ESI, Wien) (Mathematische Physik) |
| Abstract: | Abstract: Ultraproducts and Central sequence algebras of II_1 factors have been very useful tools for the structural theory of von Neumann algebras. It is therefore interesting to generalize their construction to non-tracial setting, namely to type III factors. However, due to the lack of the trace, it is not clear how to generalize the definition of ultraproucts/central sequences, and indeed there have been proposed several definitions, which look rather different to each other. In this talk I will explain that all the proposed approaches can be treated in a unified way and this unification provides strutctural results about the ultraproduct of type III factors.
In particular, it is shown that the modular flow associated with ultraproduct states is the ultraproduct of the modular flows of states, and the ultraproduct of type III factors may or may not be a factor, depending on the type. This is a joint work with Uffe Haagerup.
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| Date: | Tue, 26.11.2013 |
| Time: | 14:15 |
| Location: | Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | J. Yngvason |
| The centenary of the birth of Bruno Pontecorvo: “Bruno Pontecorvo and the neutrino” |
| Speaker: | Samoil Bilenky (JINR, Dubna) |
| Abstract: | im Rahmen des Teilchenphysikseminars |
| Date: | Thu, 28.11.2013 |
| Time: | 14:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | W. Grimus, H. Neufeld |
| Classical and Quantum Impulsive Scattering |
| Speaker: | Herbert Balasin (TU Wien) |
| Abstract: | im Rahmen des Literaturseminars für Gravitationsphysik |
| Date: | Thu, 28.11.2013 |
| Time: | 14:15 |
| Duration: | 60 min |
| Location: | Arbeitsgruppe: Gravitation, Währinger Strasse 17, Seminarraum A, 2. Stock |
| Contact: | H. Rumpf |
| The core structure of complex networks |
| Speaker: | Bernat Corominas Murtra (Med.Univ.Wien) |
| Abstract: | im Rahmen der gemeinsam veranstalteten Seminare "Komplexe Stochastische
Systeme" (Univ.Wien) und "Analyse Komplexer Systeme" (Med.Univ.Wien) |
| Date: | Fri, 29.11.2013 |
| Time: | 14:15 |
| Duration: | 90 min |
| Location: | Medizinische Universität Wien, Informatikbibliothek Bauteil 88, E 03, Spitalgasse 23 |
| Contact: | H. Hüffel, Stefan Thurner |
| Chiral Transition and Deconfinement in Magnetic QCD |
| Speaker: | Prof. Eduardo Fraga (Universidade do Estado do Rio de Janeiro ) |
| Abstract: | We review the influence of a magnetic background on the phase diagram of strong interactions and how the chiral and deconfining transitions can be affected. After some motivation, we summarize results for both transitions obtained in the framework of the linear sigma model coupled to quarks and to the Polyakov loop, and how they compare to other effective model approaches and to lattice QCD. Then we discuss the outcome of the magnetic MIT bag model that yields a behavior for the critical deconfining temperature which is compatible with recent lattice results and magnetic catalysis. The qualitative success of the magnetic MIT bag model hints to Tc being a confinement-driven quantity, and leads us to the discussion of its behavior as predicted within the 't Hooft limit of QCD, which is also in line with the most recent lattice QCD results provided that quarks behave paramagnetically. Finally, we present the first results of a perturbative calculation of the pressure in the limit of very high magnetic fields with a surprising behavior in the chiral limit.
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| Date: | Fri, 29.11.2013 |
| Time: | 16:00 |
| Duration: | 60 min |
| Location: | Vienna University of Technology, Wiedner Hauptstr. 8-10, yellow area, 10th floor, seminar room E136 |
| Contact: | Andreas Schmitt |
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