Calendar of Physics Talks Vienna

Microwave quantum optics in superconducting circuits and hybrid systems
Speaker:Yasunobu NAKAMURA (Research Center for Advanced Science and Technology, University of Tokyo)
Abstract:Artificial atoms with macroscopic dimensions (up to mm) can be realized in superconducting Josephson-junction circuits. Their large dipole moment and small dissipation enable us to study coherent interaction of such "atoms" and microwave fields confined in resonators and waveguides [1]. Microwave quantum optics with itinerant microwave provides various functionality for quantum information processing. The advanced technology of superconducting quantum circuits can also be applied to quantum state control and measurement of other physical systems. We are particularly interested in manipulating collective excitations in solid. As an example, we construct a hybrid quantum system with magnon modes in a ferromagnetic crystal. Strong coupling of a magnon mode with a superconducting qubit is demonstrated.
Date: Mon, 16.06.2014
Time: 17:30
Duration: 90 min
Location:TU Wien-Freihaus, Hörsaal 5, 2. Stock, grüner Bereich
Contact:Jörg Schmiedmayer

Dipolar forces in waveguides: Casimir physics and non-additive statistical mechanics
Speaker:Efi SHAHMOON (Weizmann Institute of Science, Israel)
Abstract:Dipolar interactions lay at the basis of a variety of phenomena in physics and chemistry, ranging from fundamental quantum vacuum forces all the way to emerging quantum technologies. This work concerns the important possibility to drastically modify these dipole-dipole interactions, thus potentially affecting much of the above phenomena: Since the interactions between dipoles are mediated by (virtual) photon modes, they can be enhanced by considering dipoles embedded in geometries that confine these modes. In this context, I will present our results on the possibilities for giant van der Waals and Casimir interactions via transmission lines and non-additive many-body physics with laser-induced interactions in optical fibers.
Date: Tue, 17.06.2014
Time: 10:30
Duration: 90 min
Location:Atominstitut, Seminarraum, Stadionalle 2, 1020 Wien
Contact:Igor Mazets

Violation of Lorentz invariance, related phenomena, and experiments
Speaker:Marco Schreck (Indiana University)
Abstract:In the past 15 years the search for a possible violation of Lorentz invariance has become one pillar in fundamental research. This talk will give an introduction to this hot and fascinating topic. First of all it will be motivated why Lorentz symmetry may be violated in the vicinity of the Planck scale. As a next step an effective framework, which describes Lorentz violation for energies much smaller than the Planck scale, shall be introduced. The latter is known as the Standard-Model Extension whose Lagrange density includes all terms consistent with the ordinary Standard Model (plus gravity) but violating Lorentz invariance. This will lead us to possible phenomena that occur in this context such as vacuum birefringence. The last part of the talk will be dedicated to examples for experiments that are used to search for Lorentz violation in nature.
Date: Tue, 17.06.2014
Time: 12:30
Duration: 50 min
Location:Univ. of Vienna, Faculty of Physics (Boltzmanngasse 5, 5th floor, Schrödinger Lecture Hall / large seminar room)

Entanglement in Quantum Field Theory and the Information Loss Paradox
Speaker:Albert Huber (Univ. Wien)
Abstract:im Rahmen des Seminars für Mathematische Physik
Date: Tue, 17.06.2014
Time: 14:15
Duration: 60 min
Location:Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:J. Yngvason, J. Schlemmer

Quantum Optics control system for single atoms experiments
Speaker:Dipl.-Ing. Maria Bernard-Schwarz (IAP & National Instruments Germany GmbH, Munich/Germany)
Abstract:The two main components for quantum optics experiments are a resonator, in our case to interact with single atoms, and computational power in order to simulate experiments, control the setup and analyze results. Our system of interest is a strongly coupled atom-cavity experiment. The goal is to develop tools for controlling the external degrees of freedom, the motion of the atom [1], as well as the internal degrees of freedom, the quantum state of the system [2]. The experimental control requires the generation of precisely timed computer-controlled measurement sequences. In order to fulfill these requirements on the hardware programming level, we use a Real-Time Operating System. This guarantees the response of control tasks within certain time periods. By implementation of a Real-Time based system, we centralize the controller, data acquisition cards, FPGAs and quantum optics analysis
Date: Tue, 17.06.2014
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. Martin Gröschl

Top-quark theory
Speaker:Sven Moch (DESY, Hamburg)
Abstract:im Rahmen des Teilchenphysikseminars
Date: Tue, 17.06.2014
Time: 16:15
Duration: 60 min
Location:Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:A. Hoang, V. Mateu

Speaker:Beatrice Franke (Max Planck Institute of Quantum Optics, Myonic Atom Spectroscopy, Garching, Germany)
Abstract:In the talk I will report on a measurement which is sensitive to exotic forces in the regime of short range spin-dependent interactions. As observable serves the ratio of the Larmor precession frequencies fn of stored ultra-cold neutrons and fHg of 199 Hg atoms in a ∼1 μT vertical magnetic holding field, where the two species precess simultaneously. Via this observable, fn can be corrected for magnetic field fluctuations, and a possible coupling between spin-polarized neutrons and unpolarized nucleons within the wall material can be investigated. Such a coupling would correspond to a short range spin-dependent interaction and be mediated by Axions or axion-like particles. The coupling propagator is proportional to the product of scalar and pseudoscalar coupling constants gS gP. From our measurement we extract gS gP λ2 < 4.4 • 10−27 m2 for interaction ranges of 10−6 m < λ < 0.07 m. The presented measurements were conducted as a "by-product" of the search for the electric dipole moment of the neutron at the Paul Scherrer Institute. Experimental details and the data analysis concept will be shown.
Date: Fri, 20.06.2014
Time: 15:30
Duration: 90 min
Location:Atominstitut, Hörsaal, Stadionallee 2, 1020 Wien
Contact:A. Abele