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Calendar of Physics Talks Vienna
| Harnessing Non-Markovian Dissipation to Control Quantum Nanodevices |
| Speaker: | Thibaut Lacroix (University of St Andrews) |
| Abstract: | Nanodevices exploiting quantum effects are critically important elements of future quantum technologies (QT), but their real-world performance is strongly limited by decoherence arising from local `environmental' interactions. Compounding this, as devices become more complex (i.e. contain multiple functional units) the `local' environments begin to overlap, creating the possibility of environmentally mediated decoherence phenomena on new time- and length-scales. Such complex and inherently non-Markovian dynamics could present a challenge for scaling up QT, but â on the other hand â the ability of environments to transfer `signals' and energy might also enable sophisticated spatiotemporal coordination of inter-component processes, as is suggested to happen in biological nanomachines, like enzymes and photosynthetic proteins. In this talk, I'll will present a fully quantum model â studied |
| Date: | Tue, 22.11.2022 |
| Time: | 10:00 |
| Duration: | 45 min |
| Location: | Seminarraum Neubau ZE01-1 |
| Contact: | Peter Rabl |
| Uniqueness of supersymmetric AdS$_5$ black holes |
| Speaker: | Sergei Ovchinnikov (Edinburgh) |
| Abstract: | The classification of anti de Sitter black holes is an open problem of central importance in holography. In this talk, I will present new advances in classification of supersymmetric solutions to five-dimensional minimal gauged supergravity. In particular, we prove a black hole uniqueness theorem within a âCalabi-typeâ subclass of solutions with biaxial symmetry. This subclass includes all currently known black hole solutions within this theory. |
| Date: | Tue, 22.11.2022 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | ZOOM link: https://tuwien.zoom.us/j/96505893692?pwd=TWNKUThEOW83anl1RDl5UDRaZVdNUT09 |
| Contact: | D. Grumiller, S. Fredenhagen, E. Battista, R. Ruzziconi |
| Theoretical formation of carbon nanomembranes under realistic conditions using classical molecular dynamics |
| Speaker: | Jürgen Schnack (Bielefeld University, Faculty of Physics Bielefeld/Germany) |
| Abstract: | Carbon nanomembranes made from aromatic precursor molecules are freestanding nanometer-thin materials of macroscopic lateral dimensions. Although produced in various versions for about two decades, not much is known about their internal structure. Here we present a systematic theoretical attempt to model the formation, structure, and mechanical properties of carbon nanomembranes using classical molecular dynamics simulations. We find theoretical production scenarios under which stable membranes form. They possess pores as experimentally observed. Their Youngâs modulus, however, is systematically larger than experimentally determined.
Alternative approaches as well as an outlook how to advance our theoretical understanding are provided
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| Date: | Tue, 22.11.2022 |
| Time: | 16:00 |
| Location: | TU Wien, Institut für Angewandte Physik, E134 1040 Wien, Wiedner HauptstraÃe 8-10 Yellow Tower âBâ, 5th floor, SEM.R. DB gelb 05 B |
| Contact: | Dr. Richard Wilhelm |
| Phenomenology with Massive Neutrinos in 2022 |
| Speaker: | Maria Gonzalez-Garcia (C.N. Yang Inst. for Theoretical Physics at Stony Brook Univ. and ICREA at the Univ. of Barcelona) |
| Abstract: | Neutrino oscillation experiments have provided us with our only direct proof of physics beyond the standard model (BSM) in the form
of lepton flavour violation in neutrino propagation due to neutrino masses and flavour mixing in the leptonic sector. In this talk I will first review the present status of neutrino masses and mixing in the minimal framework with three massive neutrinos. I will then discuss other new physics effects that can also probed with neutrino oscillations such as non standard neutrino interactions,
models with new ultralight mediators or additional sterile neutrino states. I will also comment on my personal take on the implications of these results for our clarification of the underlying BSM dynamics. |
| Date: | Tue, 22.11.2022 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultaet fuer Physik, Erwin Schroedinger-HS, Boltzmanngasse 5, 5. Stock |
| Contact: | A. Hoang, M. Procura, T. Corbett |
| qBounce: Using Gravity Resonance Spectroscopy to investigate bouncing neutrons on mirrors |
| Speaker: | Jakob Micko (TU Wien Atominstitut) |
| Abstract: | qBounce uses Ultra Cold Neutrons (UCNs) in a mechanical Ramsey type spectrometer to investigate gravity. The neutrons are trapped on the surface of mirrors by gravity leading to discrete quantum states. Transitions between these states are induced by mechanical oscillations of the mirrors in a Ramsey type fashion. Using this novel method called Gravity Resonance Spectroscopy (GRS) high precision measurements of the local acceleration of the neutron have been performed. The neutron has near zero charge and low polarizability when compared to atoms so the system is insensitive to many external influences. The experiment was comissioned in 2017 at the ILL in Grenoble and in 2018 the first proof of principle of this Ramsey type GRS was published. Improvements to the experimental setup were investigated and implemented increasing stability and precision in 2018 and 2019. Precision measureme |
| Date: | Wed, 23.11.2022 |
| Time: | 16:15 |
| Duration: | 45 min |
| Location: | Hörsaal ATI |
| Contact: | Hartmut Abele |
| LHCb SciFi Tracker - Current Status and Upgrade Plans |
| Speaker: | Carina Trippl (EPFL - Ecole Polytechnique Federale Lausanne) |
| Abstract: | A new Scintillating Fibre (SciFi) Tracker has been installed as part of the last LHCb Upgrade (2019-2022) to increase the tracking efficiency and to implement a trigger-less 40 MHz electronic readout system. The tracker is made of staggered scintillating fibres and read out by Silicon Photomultipliers (SiPMs).
At the end of the Run 3 data taking period in 2025, an integrated luminosity of L=40/fb will be reached, which is close to the SciFi Trackers design luminosity of L=50/fb.
Thus the fibre modules most affected by the radiation will be replaced during the next long shutdown (2026 - 2029). This also allows to install microlens-enhanced SiPMs to mitigate the radiation-induced ageing effects by improving the Photon Detection Efficiency (PDE).
A further ... [full abstract available here: https://indico.cern.ch/event/1220172/] |
| Date: | Wed, 23.11.2022 |
| Time: | 17:00 |
| Duration: | 60 min |
| Location: | SMI Seminarraum, Kegelgasse 27, 3. Stock |
| Contact: | Eberhard Widmann, Martin Simon |
| Non-smooth Spacetimes, Quantum Field Theory, and Microlocal Analysis |
| Speaker: | Yafet Erasmo Sanchez Sanchez (Hamburg) |
| Abstract: | In this talk, I will present the quantisation of the linear scalar field when the background spacetime metric is not smooth.
The analysis of quantum fields in spacetimes, where the metric is not smooth, has two primary motivations.
First, there are several models of physical phenomena that require spacetime metrics with finite regularity.
Second, the analysis of the well-posedness of Einsteinâs equations, viewed as a system of hyperbolic PDEâs requires spaces with finite regularity.
I will focus mainly on the microlocal aspects of the causal propagator and the two-point function of ground states, and the techniques used to overcome the lack of smoothness.
The talk will be based on arXiv:1910.13789 and arXiv:2207.01429 |
| Date: | Thu, 24.11.2022 |
| Time: | 15:15 |
| Duration: | 60 min |
| Location: | ZOOM https://univienna.zoom.us/j/6540036841?pwd=SytyVkZJZzNyRG9lMm13ejlHeHRRUT09 |
| Contact: | P. Chrusciel, D. Fajman |
| How satellites can help to solve the greatest questions of modern physics? |
| Speaker: | Hansjoerg Dittus, Universitaet Bremen (DKPI - TU Wien) |
| Abstract: | The presentation will report on so far unexplained observations of deviations of spacecraft trajectories and discuss the possibilities for future missions and space experiments in gravitational and quantum physics. |
| Date: | Thu, 24.11.2022 |
| Time: | 18:30 |
| Duration: | 60 min |
| Location: | TUtheSky Meeting Hall, Getreidemark 9, 1060 Vienna, https://indico.cern.ch/event/1207521/registrations/87896/ |
| Contact: | Hartmut Abele |
| Emerging dissipative phases in a superradiant quantum gas |
| Speaker: | Oded Zilberberg (Universität Konstanz) |
| Abstract: | Exposing a many-body system to external drives and losses can deeply modify its phases. Beside their fundamental interest, driven-dissipative systems prompt new paradigms for material engineering. A prime example is given by hybrid systems in which tuning of the elementary excitations is obtained by coupling matter to light. In this perspective, gaining conceptual understanding on how the microscopic properties of such systems can be tuned by the coupling to the environment is of primary interest. However, it is often a challenge to find platforms combining well-defined, tunable coherent and dissipative channels and, at the same time, the access to microscopic observables of the system. I will introduce a light-matter many-body system offering these possibilities, based on a Bose-Einstein condensate that is strongly coupled to an optical cavity. In a related experiment from the Esslinger |
| Date: | Fri, 25.11.2022 |
| Time: | 10:00 |
| Duration: | 45 min |
| Location: | ATI Hörsaal/https://tuwien.zoom.us/j/93672218922?pwd=dEZNQ2liVzRNNURvNmVWVE5KUWRiQT09 |
| Contact: | Julian Leonard |
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