Calendar of Physics Talks Vienna

Analytic bootstrap for operators with large spin
Speaker:Kallol Sen (Bangalore, Indian Inst. Sci.)
Abstract:Large spin operators manifest themselves when we take the Lightcone limit in the bootstrap equation for four scalar operators. We consider such large spin operators and analyze how the twist changes if we add a stress tensor to the spectrum. Observe that the correction to the twist of these operators depends crucially on the presence of the stress tensor in a particular way. In some limit when the spin of these operators is much larger than the twist of these operators, the correction (anomalous dimensions) match with the holographic predictions. We also observe some more interesting facts about these anomalous dimensions.
Date: Mon, 12.10.2015
Time: 10:00
Duration: 60 min
Location:SEM, TU Wien, Freihaus, yellow tower, 3rd floor (Wiedner Hauptstr. 8-10, A-1040 Vienna)
Contact:Daniel Grumiller

Diamond photonics & phononics: creating interfaces for colour centres in diamond
Speaker:Christoph Becher (Universität des Saarlandes, Saarbrücken, Germany)
Abstract: The coupling of single colour centres in diamond to photons and phonons is considered an important step towards integrated solid-state devices for quantum information processing and quantum sensing. For interfacing to photons I will present two routes for the deterministic coupling of single nitrogen- (NV) or silicon-vacancy (SiV) centres to optical cavities at the micro- and nano-scale using either fiber-based, tunable, Fabry-Perot-type resonators or photonic crystal cavities directly fabricated in the diamond material. We observe channeling of the spontaneous emission into the cavity modes, paving the way for a high-speed single photon sources and optical interfaces for quantum information. Additional coupling to phonons can be achieved using a photonic and phononic crystal (phoxonic crystal, PxC) which is a periodically patterned material that at the same time localizes optical and m
Date: Mon, 12.10.2015
Time: 17:30
Duration: 60 min
Location:Ernst-Mach Hörsaal, 2. Stck.,Strudlhofgasse 4, 1090 Wien
Contact:www.coqus.at / Christina Becker

Development of a Beam-Gas Vertexing demonstrator at the LHC
Speaker:Mariana Rihl (CERN)
Abstract:The Beam-Gas Vertex detector is a non-destructive instrument to measure the transverse beam sizes and shapes at the Large Hadron Collider (LHC). It is based on a technique that was pioneered in the LHCb experiment, where tracks of charged particles produced in inelastic beam-gas interactions, are used to reconstruct beam-gas vertices. The spatial vertex distributions give an image of the transverse beam shapes. [paragraph omitted due to space limitations] An overview and status of the project (vacuum system, detector and readout system) will be presented. Full abstract: https://indico.smi.oeaw.ac.at/event/114/
Date: Wed, 14.10.2015
Time: 17:00
Duration: 60 min
Location:Stefan-Meyer-Institut Hörsaal (2.08), Boltzmanng. 3, 1090, Wien
Contact:Ken Suzuki

Evanescently Trapped Atoms for Quantum Information
Speaker:Steven L. Rolston (Co-Director, Joint Quantum Institute, Dept. of PhysicsUniversity of Maryland, USA)
Abstract:Photons are the ideal carriers of quantum information and atoms the ideal quantum memory. By trapping atoms in the evanescent field of optical nanostructures, it is possible to create atomic systems with excellent coupling to photons propagating in optical fibers. I will discuss experiments at the JQI with atoms trapped on optical nanofibers, inspired by work in Vienna, progress toward integrated optical waveguides capable of trapping atoms, and efforts towards hybrid quantum systems coupling atoms, photons, and superconducting qubits.
Date: Fri, 16.10.2015
Time: 15:30
Location:Atominstitut, Hörsaal, Stadionallee 2, Wien 2
Contact:Arno Rauschenbeutel