Calendar of Physics Talks Vienna

Information processing in stochastic neuromorphic circuits
Speaker:Karlheinz MEIER (Kirchhoff-Institut für Physik, Universität Heidelberg)
Abstract:The brain is a universe of 100 Million cells interacting through 1000 Trillion constantly changing synapses. Biological recordings and simulations on conventional super-computers do only provide limited access to this complex systems. In the lecture we will report on an alternative approach to information processing in the brain based on physical models of neural circuits. Experimental test of theories based on the stochastic dynamics of brain networks on such systems will be discussed.
Date: Mon, 17.06.2013
Time: 17:30
Location:Technische Universität Wien, Freihaus, Hörsaal 5 (2. Stock, grüner Bereich), Wiedner Hauptstraße 8, 1040 Wien
Contact:J. Schmiedmayer

From Single Atoms to Solids - Quantum Chemistry in Solid State Physics
Speaker:Paul Tiwald (TU Wien)
Abstract:I will give an introduction to quantum chemistry methods and their application to solid state and surface physics within the embedded cluster approach. Two topics currently under investigation will be presented. The first topic is the F-center in Lithium Fluoride (LiF), a point defect giving rise to bound electronic states. The second topic is the interaction dynamics and the charge transfer of a proton approaching a LiF surface.
Date: Tue, 18.06.2013
Time: 12:30
Duration: 60 min
Location:TU Vienna, Wiedner Hauptstr. 8-10, yellow area, 10th floor, seminar room E136
Contact:F. Brünner, P. Köhler, A. G. Passegger, S. Stetina - www.univie.ac.at/lunch-seminar

Self-assembled molecular structures at metal surfaces: conformation, charge transfer and functionality
Speaker:Mr. Allegretti Francesco (Surface and Interface Physics Department, TU Munich)
Abstract:The self-assembly of functional molecules at surfaces is a powerful tool to engineer novel low-dimensional architectures with tailored properties, thanks to the versatile library of tectons that organic chemistry can provide. This approach is of interest in many fields of fundamental and applied research, such as heterogeneous catalysis, dye-sensitized solar cells, molecular electronics and spintronics, gas sensing. In my talk I will focus on two classes of systems selected from our current research, and I will show the interplay of physical phenomena that occur when relatively complex (at least from a surface science perspective) molecules adsorb and self-assemble on surfaces. I will first present our recent work on tetrapyrrole macrocyclic compounds on coinage metal surfaces, which shows the competition of different interactions, electronic and conformational changes,
Date: Tue, 18.06.2013
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:Ao.Univ.Prof. Dr. Josef Redinger

Time functions, conformal factors and Cauchy surfaces of bounded geometry
Speaker:Olaf Müller (Regensburg)
Abstract:im Rahmen des Literaturseminars
Date: Thu, 20.06.2013
Time: 14:00
Duration: 60 min
Location:Arbeitsgruppe: Gravitation, Währinger Strasse 17, Seminarraum A, 2. Stock
Contact:P. Chrusciel

K semileptonic form factors from lattice QCD
Speaker:Elvira Gamiz (Univ. of Granada)
Abstract:im Rahmen des Teilchenphysikseminars
Date: Thu, 20.06.2013
Time: 14:15
Duration: 60 min
Location:Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:G. Ecker, H. Neufeld

(Entanglement) Entropy in three-dimensional higher spin theories
Speaker:Juan Jottar (Amsterdam U.)
Abstract:A holographic correspondence has been recently developed between higher spin theories in AdS_3 and (1+1)-dimensional CFTs with extended symmetries. In this framework, black hole solutions in the bulk theory are dual to thermal equilibrium states with non-trivial higher spin charges and chemical potentials. We discuss the calculation of the higher spin black hole entropy from an appropriate Euclidean variational principle, and provide a generalization of the Cardy entropy formula for these setups. Additionally, we present a proposal to compute entanglement entropy in the dual CFTs via holography, thus extending the Ryu-Takayanagi prescription to higher spin theories in AdS_3.
Date: Thu, 20.06.2013
Time: 16:00
Duration: 60 min
Location:SEM 136 (Freihaus, Wiedner Hauptstrasse 8-10), Institute for Theoretical Physics, Vienna University of Technology
Contact:Daniel Grumiller

Solid-state light-matter interfaces on the quantum test bench
Speaker:Christoph CLAUSEN (GAP-Optique, Université de Genève)
Abstract:Solid-state light-matter interfaces based on crystals doped with rare-earth ions have shown great progress in recent years, heading towards quantum technology applications. During my PhD, I performed a series of experiments that tested the suitability of an atomic frequency comb light-matter interface, implemented in a Nd:YSO crystal, for the storage of quantum information. To this end, a dedicated source of entangled photons has been developed, and the storage and retrieval of quantum correlations and entanglement been studied. The experiments show the successful transfer of photonic entanglement to the crystal, and the generation of a matter-matter entangled state between two crystals. These are two of the main steps in a quantum repeater protocol. At the end of my talk, I shall briefly present the current progress towards the teleportation of a polarization qubit into the light-matter interface.
Date: Fri, 21.06.2013
Time: 15:30
Location:TU Wien Atominstitut, Hörsaal, Stadionallee 2, 1020 Wien
Contact:A. Rauschenbeutel