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Calendar of Physics Talks Vienna
| Towards Photonic Quantum Network based on Spin Qubits in Diamond |
| Speaker: | Tim Schröder (MIT) |
| Abstract: | We demonstrate the deterministic creation of negatively charged nitrogen-vacancy spin qubits (NVs) at the mode maximum of diamond photonic crystal cavities with a yield of about 1.1 ± 0.2 NVs per cavity, Purcell induced enhancement of the zero-phonon-line spontaneous emission rate greater than 60, and NV electron spin coherence time exceeding 200 µs. Furthermore, we show the efficient integration of NVs in diamond nanostructures into photonic on-chip circuits. These NV systems and their efficient photonic integration represent a step towards efficient on-chip solid-state based spin-photon interfaces paving the way towards scalable quantum information processing. |
| Date: | Mon, 16.03.2015 |
| Time: | 15:00 |
| Duration: | 90 min |
| Location: | Atominstitut, Hörsaal, Stadionallee 2, Wien 2 |
| Contact: | Arno Rauschenbeutel |
| Algebraic operations from topological field theory |
| Speaker: | Gregor Schaumann (MPI Bonn) |
| Abstract: | Topological field theories provide strong connections between algebra and topology. The aim of this talk is to summarize some recent developments along theses lines.
In the case of 3-dimensional TFTs, diagrammatic representations allow one to get intuition for higher categorical traces, symmetrized products and center constructions.
This is joint work with Christoph Schweigert und Jürgen Fuchs. |
| Date: | Tue, 17.03.2015 |
| Time: | 11:00 |
| Duration: | 60 min |
| Location: | ESI |
| Contact: | Nils Carqueville |
| Optical nonlinear control at a very low power in |
| Speaker: | Takasumi Tanabe (Keio University - Japan) |
| Abstract: | Ultrahigh-Q nano- and microcavities enable strong interaction between light and
matter. Among various microcavities, photonic crystal nanocavities and silica
whispering gallery mode microcavities exhibit the highest Q/V, where V is the mode
volume of the cavity.
In the first half of my talk, I will discuss on some applications using photonic crystal
nanocavity [1] as such as an all-optical switch [2]. I will also show some of our
preliminary result on the demonstration of the ultrahigh-Q nanocavity fabricated with
CMOS process, as well as the dynamic formation of a high-Q nanocavity by using
tapered fiber and a photonic crystal waveguide.
In the second half of my talk, I will share our recent results on high-Q whispering
gallery mode microcavity system [3, 4]. I will discuss on the demonstration of Kerr
switching at lowest possible power [5], which is not possible with cavities made of
semiconductors such as photonic crystals. I will also show the generation of optical
Kerr comb and harmonic mode locking using the same cavity, and discuss the
theoretical background of the mode-locking in a microcavity system based on Lugiato-
Lefever equation [5]. |
| Date: | Tue, 17.03.2015 |
| Time: | 11:15 |
| Duration: | 90 min |
| Location: | Atominstitut, Seminarraum, Stadionallee 2, Wien 2 |
| Contact: | Arno Rauschenbeutel |
| Real time observations of nanowire growth in scanning electron microscope |
| Speaker: | Miroslav Kolíbal (CEITEC BUT, Brno University of Technology, Brno/Czech Republic) |
| Abstract: | The nanowire shape (cross-section, sidewalls’ orientation etc.) and orientation plays a major role in determining electrical transport or sensing properties of nanowire-based devices. The ability to fully control the nanowire morphology is, of course, based on our understanding of the growth process. In this respect, in-situ Transmission Electron Microscopy (TEM) studies have provided vital information on this issue.
In this contribution, I will present our results on the vapor-liquid-solid (VLS) germanium nanowire growth by evaporation inside a SEM vacuum chamber. Compared to TEM, scanning electron microscopy (SEM) can easily give three-dimensional information of the growth scenario. As the group IV nanowires grown by evaporation are highly faceted, I will focus on effects where SEM can give substantial information. In particular, the initial formation of the growth interface between t |
| Date: | Tue, 17.03.2015 |
| Time: | 16:00 |
| Location: | Technische Universität Wien, Institut für Angewandte Physik, E134 yellow tower „B“, 5th floor, Seminarraum 134A (room number DB05L03) 1040 Wien, Wiedner Hauptstraße 8-10 |
| Contact: | Ao.Univ.Prof. Dr. Peter Varga |
| The Standard Model Effective Theory and Dimension 6 Operators |
| Speaker: | Prof. Aneesh V. Manohar (University of California, San Diego) |
| Abstract: | 3. Vorlesung im Rahmen der Schrödinger-Gastprofessur:
Effective theory methods are applied to the standard model to study
the effects of new physics in a model independent way. The talk
outlines some recent results on the renormalization of dimension
6 operators, and the implications for processes such as Higgs decay
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| Date: | Tue, 17.03.2015 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | A. Hoang, H. Neufeld |
| Solutions to the Einstein constraint equations with constant mean curvature |
| Speaker: | Romain Gicquaud (Université de Tours, France) |
| Abstract: | im Rahmen des Seminars in Geometric Analysis and Physics
(GAP Seminar) |
| Date: | Thu, 19.03.2015 |
| Time: | 11:00 |
| Duration: | 60 min |
| Location: | Arbeitsgruppe Gravitation, Währinger Strasse 17, Seminarraum Kernphysik, 5. Stock, Zi. 504-506, 1090 Wien |
| Contact: | M. Bauer (Fak. Math, U.V.), V. Branding (Fak. Math, T.U.), D. Fajman (Fak. Phys, U.V.), J. Joudioux (Fak. Phys, U.V.) |
| Quantization of conical spaces in 3D gravity |
| Speaker: | Joris Raeymaekers (Prague, Inst. Phys.) |
| Abstract: | see http://arxiv.org/abs/1412.0278 |
| Date: | Thu, 19.03.2015 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | SEM 136, TU Wien, Freihaus, 10th floor (Wiedner Hauptstr. 8-10, A-1040 Vienna) |
| Contact: | Daniel Grumiller |
| Solutions of the conformal constraint equations with non-constant mean curvature |
| Speaker: | Romain Gicquaud (Tours) |
| Abstract: | im Rahmen des Literaturseminars für Gravitation: Constructing broad classes of (physically relevant) initial data for the Cauchy problem is
an important issue in general relativity. From the Gauss and Codazzi
equations, the 0th order initial data (the metric induced on a Cauchy
surface) and the first order initial data (the second fundamental form
of the Cauchy surface) cannot be chosen arbitrarily: they have to
satisfy some constraint equations. One of the main methods for studying
these equations is the conformal method which was highly successful for
constructing and classifying constant mean curvature(CMC) initial data. However, constructing non CMC initial data
remains a widely open subject. In this talk I will describe recent
results on the construction of solutions to the constraint equations
with non constant mean curvature by the conformal method. |
| Date: | Thu, 19.03.2015 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Arbeitsgruppe Gravitation, Währinger Strasse 17, Seminarraum A, 2. Stock, 1090 Wien |
| Contact: | P.T. Chrusciel |
| Strongly coupled phases of N = 1 S-duality |
| Speaker: | Inaki Garcia-Etxebarria (MPI Munich) |
| Abstract: | We have recently argued for the existence of a natural
generalization of 4d N=4 SL(2,Z) duality, which applies to a vast class
of N=1 theories arising from branes at singularities. I will review the
motivation and evidence for the proposal, and then discuss some recent
developments which indicate that intrinsically strongly coupled field
theories play a fundamental role in the duality behavior of these N=1
theories. |
| Date: | Thu, 19.03.2015 |
| Time: | 16:00 |
| Duration: | 60 min |
| Location: | SEM 136, TU Wien, Freihaus, 10th floor (Wiedner Hauptstr. 8-10, A-1040 Vienna) |
| Contact: | Johanna Knapp and Timm Wrase |
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