Calendar of Physics Talks Vienna

Nature's shortest length
Speaker:Georgi Dvali (Theoretische Physik, LMU München & CERN Genf)
Abstract:We discuss the concept of the nature's shortest length-scale, and its implications for the fundamental question of UV-completion and for phenomenology and cosmology.
Date: Mon, 28.11.2011
Time: 17:30
Duration: 60 min
Location:University of Vienna, Lise-Meitner-Hörsaal, Boltzmanngasse 5, 1st floor.
Contact:Dr. Christiane Losert / Univ. of Vienna

Superfluidity in dense quark matter
Speaker:Stephan Stetina (TU Wien)
Abstract:At very high densities, the ground state of quark matter is a colour superconductor in the "colour flavour locked" (CFL) state. In nature, such densities are realized in compact stars. Since CFL is also a superfluid, properties of compact stars might depend on the hydrodynamics of CFL quark matter. I will therefore discuss, how superfluid hydrodynamics in such a system emerge from the corresponding microscopic theory.
Date: Tue, 29.11.2011
Time: 12:30
Duration: 60 min
Location:Uni Wien ( Boltzmanngasse 5, 5th floor, Schrödinger HS / large seminar room )
Contact:Sabine Ertl

p-Electron Magnetism in anion doped BaTiO3-xXx (X=C,N,B) and CdS
Speaker:Ao.Univ.Prof. Dr. Peter Mohn (TU Wien, IAP and Center for Computational Materials Science)
Abstract:We present VASP calculations using the HSE functional for carbon, nitrogen, and boron doped BaTiO3-xXx (X=C,N,B) and CdS1-xYx (Y= main group element). We calculate supercells and replace one oxygen atom by C,N, or B or a main group element for S in CdS. In the perovskite for all three substituents we find a magnetically ordered groundstate which is insulating for C and N and halfmetallic for B. The changes in the electronic structure between the undoped and the doped case are dominated by the strong crystal field effects together with the large band splitting for the impurity p-bands. Using an MO picture we give an explanation for the pronounced changes in the electronic structure between the insulating non-magnetic state and the as well insulating magnetic state for doped BaTiO3. For CdS we also find in most cases magnetic order, either halfmetallic or indulating. p-element doped perovskites and CdS could provide a new class of materials for various applications ranging from spin-electronics to magneto-optics.
Date: Tue, 29.11.2011
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.Prod. Dr. Peter Mohn

Hard pion chiral perturbation theory and charmonium decays
Speaker:Ilaria Jemos (Univ. Wien)
Abstract:im Rahmen des Teilchenphysikseminars
Date: Thu, 01.12.2011
Time: 14:15
Duration: 60 min
Location:Fakultät für Physik, Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:H. Neufeld

Estimates of the asymptotically hyperbolic mass
Speaker:Mattias Dahl (Stockholm)
Abstract:im Rahmen des Literaturseminars
Date: Thu, 01.12.2011
Time: 14:15
Duration: 60 min
Location:Arbeitsgruppe: Gravitation, Währinger Strasse 17, Seminarraum A, 2. Stock
Contact:R. Beig

Recent Developments in Socio-Dynamics
Speaker:Michael Szell (Med.Uni Wien)
Abstract:im Rahmen der gemeinsam veranstalteten Seminare "Komplexe Stochastische Systeme" (Univ. Wien) und "Analyse Komlexer Systeme" (Medizinische Univ.Wien)
Date: Fri, 02.12.2011
Time: 14:00
Duration: 90 min
Location:Medizinische Univ., Bauteil 88,
Contact:H. Hüffel, Stefan Thurner

The interplay between ultracold atoms and quantum electronic systems
Speaker:Mark Fromhold (Midlands Ultracold Atom Research Centre, School of Phyiscs and Astronomy, University of Nottingham)
Abstract:In this talk, I will explore the effect of quantum electronic components, fabricated in a two-dimensional electron gas, on nearby ultracold atoms. Conversely, I will consider how ultracold atoms may both control and image electrons in semiconductor nanostructures. I will present calculations, which predict that current through a two-dimensional electron gas can trap ultracold atoms less than 1 micron away with orders of magnitude less spatial noise than for a metal trapping wire. This noise reduction, combined with low Casimir-Polder attraction, may enable the creation of hybrid atom chip structures, which exploit small changes in the conductance of quantum electronic devices to manipulate the trapped atoms. For example, activating a single quantized conductance channel in a quantum point contact can split a Bose-Einstein condensate for atom interferometry. In turn, the condensate itself offers unique structural and functional imaging of quantum devices and transport. Finally, I will consider the prospects of using ultracold atoms to enable re-writable matter-wave lithography of quantum electronic devices.
Date: Fri, 02.12.2011
Time: 15:30
Location:Hörsaal Aotminstitut, Stadionallee 2. 1020 Wien
Contact:J. Schmiedmayer