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Calendar of Physics Talks Vienna
| Advanced experimental and modeling approaches to understand and predict better corrosion of metals |
| Speaker: | Hermann Terryn (Vrije Universiteit Brussel, Research Group SURF Electrochemical Surface Engineering, Materials and Chemistry Department MACH, Brussels/Belgium) |
| Abstract: | In the advanced materials industry, there is a clear trend towards more sustainable concepts, and this is certainly also the case for metals. They take a prominent position in the materials market thanks to their multifunctionality and structural and mechanical properties. However, metals are prone to corrosion, and therefore often organic coatings are applied to extend their lifetime. The search for organic coated metals with higher multifunctionality and extended lifetime goes together with the search for more sustainable material concepts in the context of the REACH regulation.
Nowadays, materials are developed for providing components with a lifetime ranging from 10 to 25 years. The lifetime of a material highly depends on its exposure to the environment inducing ageing processes. In the current state of the art, lifetime and ageing assessment are performed by means of experiments, c |
| Date: | Mon, 21.01.2019 |
| Time: | 10:00 |
| Location: | TU Wien, Institut für Angewandte Physik, E134 1040 Wien, Wiedner Hauptstraße 8-10 Yellow Tower „B“, 4th floor, SEM.R. DB gelb 04 (105A) |
| Contact: | Univ.Prof. Markus Valtiner |
| Problems in the Lifshitz theory of dispersion forces |
| Speaker: | Vladimir M. Mostepanenko (Russian Academy of Sciences, Saint Petersburg, Russia) |
| Abstract: | The Lishitz theory describes the van der Waals and Casimir forces which
arise between two closely spaced material bodies due to the zero-point
and thermal fluctuations of the electromagnetic field. A lot of precise
measurements of the Casimir force performed during the last two decades
revealed a puzzle. The theoretical predictions have been found in
agreement with the measurement data only under a condition that in
computations one disregards the relaxation properties of conduction
electrons for metals and the dc conductivity for dielectrics. On the
theoretical side it was found that if both these effects
are included, one arrives to contradictions with thermodynamics.
Possible resolution of this puzzle is discussed.
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| Date: | Mon, 21.01.2019 |
| Time: | 14:15 |
| Duration: | 60 min |
| Location: | TU Wien, Freihaus HS 7, Wiedner Hauptstr. 8-10, 2nd floor, 1040 Wien |
| Contact: | Anton Rebhan |
| CoQuS colloquium with Martin Plenio, University Ulm |
| Speaker: | Martin Plenio & CoQuS student Yuri Minoguchi (CoQuS) |
| Abstract: | Diamond Quantum Devices.
From Quantum Simulation to Medical Imaging.
A perfect diamond is transparent for visible light but there are famous diamonds, such as the famous Oppenheim Blue or the Pink Panther worth ten's of millions of dollar, which have intense colour. An important source of colour in diamond are lattice defects which emit and absorb light at optical frequencies and may indeed possess a non-vanishing ground state electronic spin. I will explore the physics of one of these defects, the nitrogen vacancy center, and show how we can manipulate its electronic spin to develop quantum simulators, nanoscale quantum sensors and sources of nuclear hyperpolarisation. Applications of such devices range from sensing in biology to medical imaging. |
| Date: | Mon, 21.01.2019 |
| Time: | 17:00 |
| Location: | Lise-Meitner Lecture Hall, Boltzmanngasse 5, 1090 Vienna |
| Contact: | CoQuS office |
| Exceptional geometry of supersymmetric AdS vacua |
| Speaker: | Emanuel Malek - Max Planck Institute for Gravitational Physics, Potsdam |
| Abstract: | In this talk I will show how exceptional field theory can be used to construct 1/2-maximally supersymmetric AdS vacua of 10/11-dimensional supergravity and their consistent truncations.In particular I will show how to easily recover the class of infinitely-many supersymmetric AdS_7 vacua of massive IIA and AdS_6 vacua of IIB which were recently constructed in the literature.Next I will show how this framework can be used to immediately obtain the "minimal" consistent truncation around these AdS vacua in which only the gravitational supermultiplet of the lower-dimensional supergravity is kept.Finally I will classify all possible consistent truncations around these AdS vacua containing additional matter multiplets.I will thus show there are no consistent truncations with vector multiplets for the AdS_7 vacua with Roman's mass and give precise differential conditions for the AdS_6 vacua ... |
| Date: | Tue, 22.01.2019 |
| Time: | 13:45 |
| Duration: | 60 min |
| Location: | TU Wien, Getreidemarkt 9, Maschinenbaugebäude, 1. Stock, HS Kleiner Schiffbau |
| Contact: | S. Fredenhagen, D. Grumiller |
| Removing infrared divergences from perturbative amplitudes |
| Speaker: | George F. Sterman (SUNY, Stony Brook) |
| Abstract: | 4. Vorlesung im Rahmen der Schrödingen-Gastprofessur:
It may be useful to separate perturbative amplitudes into universal infrared-sensitive terms,
which sometimes can be computed exactly, plus infrared-finite remainders, which can in
principle be computed numerically. Two-loop scalar diagrams illustrate how such a procedure could work.
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| Date: | Tue, 22.01.2019 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | A. Hoang, H. Neufeld |
| Controlling light by light |
| Speaker: | Shalva Amiranashvili (Weierstraß Institut, Berlin) |
| Abstract: | Studies on ultrashort pulses in nonlinear optical fibers provided a number of exotic applications including radiation at negative frequencies, analogue black holes, singular solitons, and optical rogue waves. In this talk, we will discuss a new possibility to manipulate optical solitons using the so-called optical event horizons. Here, the soliton serves as an impenetrable potential barrier for a properly chosen pump wave. The wave is scattered thus transmitting its energy to the soliton. The process can be used to compress or decompress the soliton and to stabilize its frequency. |
| Date: | Wed, 23.01.2019 |
| Time: | 14:15 |
| Location: | Seminar room FH gelb 10, Institute for Theoretical Physics – Vienna University of Technology, Wiedner Hauptstraße 8 – 10, 10th floor, B (yellow tower) |
| Contact: | Joachim Burgdörfer |
| Band structure of HgTe-based topological insulators |
| Speaker: | Sergey Tarasenko (Ioffe Institute, St. Petersburg, Russia) |
| Abstract: | Quantum wells (QWs) and thin films based on band-inverted material HgTe have been attracting growing attention since they can realize 2D and 3D topological insulators. Here, we discuss the fine structure and optical properties of the bulk and edge states in 2D topological insulators based on HgTe QWs. A natural interface and bulk inversion asymmetry, reflecting the real atomistic structure of zinc-blende-type QWs, leads to the spitting of the Dirac states in HgTe QWs. The inversion symmetry drastically modifies the dispersion, magnetic and optical properties of the helical edge states. In particular, it enables the electro-dipole optical transitions between the spin branches of the edge channel and gives rise to the linear and circular dichroism associated with the edge states as well as the circular and linear edge photocurrents. |
| Date: | Wed, 23.01.2019 |
| Time: | 16:00 |
| Location: | Freihaus, Sem.R. DC rot 07 OG |
| Contact: | Andrei Pimenov |
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