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Calendar of Physics Talks Vienna
| Analysing the optical nonlinearity of a cavity-like subwavelength atomic array (Vienna Theory Lunch Seminar) |
| Speaker: | Simon Panyella Pedersen (TU Wien) |
| Abstract: |
Sub-wavelength arrays of quantum emitters offer an interesting approach to coherent light-matter interfacing, using ultracold atoms or two-dimensional solid-state quantum materials. The combination of collectively suppressed photon-losses and emerging optical nonlinearities due to strong photon-coupling to mesoscopic numbers of emitters holds promise for generating nonclassical light and engineering effective interactions between freely propagating photons. In my talk I will describe the interaction between photons and a specific configuration of two-level atoms, namely two parallel 2D arrays individually acting like mirrors and together forming a cavity-like system. [[... full abstract https://lunch-seminar.univie.ac.at ]] |
| Date: | Tue, 18.06.2024 |
| Time: | 12:30 |
| Duration: | 75 min |
| Location: | TU Wien: Wiedner Hauptstr. 8-10, yellow area, 10th floor, seminar room DB10E11 |
| Contact: | Florian Lindenbauer |
| Fuzzy de Sitter spaces in three and four dimensions |
| Speaker: | Ilija Buric (University of Pisa) |
| Abstract: | We discuss noncommutative (anti) de Sitter spaces in two, three and four dimensions. After recalling their definitions, we analyse coordinate spectra, coherent states, invariant vacua and eigenfunctions of the Laplace-Beltrami operator. Our results pave the way for the analysis of late time correlation functions in QFTs on fuzzy dS backgrounds, of potential relevance for inflationary cosmology. The talk is based on joint works with Bojana BrkiÄ, Maja BuriÄ and DuÅ¡ko Latas. |
| Date: | Tue, 18.06.2024 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | TU Wien Freihaus, Wiedner Hauptstrasse 8, 3rd floor, yellow tower, Sem. R. DB gelb 03 |
| Contact: | S. Fredenhagen, D. Grumiller, T. Tran, A. Fiorucci |
| Towards Supersolids of Ultracold Calcium Monofluoride Molecules |
| Speaker: | Philipp Groà (TU Wien Atominstitut) |
| Abstract: | The production of ultracold molecular quantum gases promises to add long-range dipolar interaction to the quantum simulation toolbox. Here we first show theoretically that such dipolar interactions can lead to the formation of new phases of matter in bulk molecular Bose-Einstein condensates, such as droplet states and supersolids. We discuss the possibilities that bulk molecular Bose-Einstein condensates may open up for dipolar many-body physics in the near future. Building on our work on dipolar droplets and supersolids that form from weakly dipolar atoms, we show how ultracold molecules and microwave shielding can provide fundamentally new insights into these exotic states of matter. Second, we present a setup to realize these phases of matter in an experiment. In this setup we work with calcium monofluoride molecules, which are characterized by large electric dipole moments and well-e |
| Date: | Wed, 19.06.2024 |
| Time: | 16:15 |
| Duration: | 45 min |
| Location: | Helmut Rauch Lecture Hall |
| Contact: | Maximilian Prüfer |
| Small Schwarzschild de Sitter black holes, quantum extremal surfaces and islands |
| Speaker: | Kaberi Goswami (Chennai Mathematical Institute (CMI)) |
| Abstract: | In arxiv: 2312.05604 we have studied 4-dimensional
Schwarzschild de Sitter black holes in the regime where the black hole mass is small compared with the de Sitter scale, following arXiv:2207.10724
[hep-th]. The de Sitter temperature is very low compared with that of
the black hole. We consider the future boundary as the location where
the black hole Hawking radiation is collected. Using 2-dimensional
tools, we find unbounded growth of the entanglement entropy of radiation
as the radiation region approaches the entire future boundary. Self-consistently including appropriate late time islands emerging just
inside the black hole horizon leads to a reasonable Page curve. We also
discuss other potential island solutions which show inconsistencies.
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| Date: | Thu, 20.06.2024 |
| Time: | 15:00 |
| Duration: | 60 min |
| Location: | TU Wien, Freihaus, Seminar room on the 10th floor |
| Contact: | Daniel Grumiller, Iva Lovrekovic |
| Waveguide optoacoustics for quantum technologies and neuromorphic photonic computing |
| Speaker: | Birgit Stiller (Max-Planck Institute of Light) |
| Abstract: | Photonics has the potential to advance modern quantum technologies and high-speed applications such as communications and the processing of large amounts of data. However, to replace or improve the well-established systems with photonic solutions, there is still a way to go. A promising approach to manipulate light all-optically is to use the link of optical waves with acoustic vibrations. Our research experimentally investigates how traveling sound waves can be used to process states of light in the classical and quantum regime.
Via the nonlinear effect of stimulated Brillouin scattering (SBS), acoustic waves can be created all-optically by counter-propagating optical signals. With help of acoustic waves, we implement several building blocks for photonic machine learning, such as a recurrent operator [1] and a nonlinear activation function [2]. We experimentally demonstrate a temporary |
| Date: | Fri, 21.06.2024 |
| Time: | 10:00 |
| Duration: | 45 min |
| Location: | Helmut Rauch Hörsaal ATI |
| Contact: | Eliza Agudelo Ospina |
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