|
Calendar of Physics Talks Vienna
| Quantum optomechanics experiments with photonic crystals |
| Speaker: | Simon Gröblacher (TU Delft) |
| Abstract: | Mechanical oscillators coupled to light via the radiation pressure force have attracted significant attention over the past years for allowing tests of quantum physics with massive objects and for their potential use in quantum information processing. Recently demonstrated quantum experiments include entanglement and squeezing of both the mechanical and the optical mode. So far these quantum experiments have almost exclusively operated in a regime where the light field oscillates at microwave frequencies. Here we would like to discuss a recent experiment where we demonstrate non-classical mechanical states by coupling a mechanical oscillator to single optical photons. These results are a promising route towards using mechanical systems as quantum memories, for quantum communication purposes and as light-matter quantum interfaces. In addition, we will also discuss efforts to perform these |
| Date: | Mon, 02.05.2016 |
| Time: | 17:30 |
| Duration: | 60 min |
| Location: | HS 7, Schütte-Lihotzky, Karlsplatz 13, Vienna |
| Contact: | www.coqus.at / Christina Becker |
| A solvable non-trivial QFT in 4 dimensions |
| Speaker: | Harald Grosse (Univ. Wien) |
| Abstract: | im Rahmen des Seminars für Mathematische Physik: A 4 dim. QFT needs regularization and renormalization.
I first discribe these concepts. We mention the UV, the IR and the Landau ghost problem.
Next we turn to the formulation of a noncommutative QFT, which becomes renormalizable
after identifying a fourth relevant/marginal operator. The beta function of the coupling
constant vanishes and a nonperturbative construction was possible and will be explained.
The model is nontrivial and all Schwinger functions are obtained from the solution of a
nonlinear integral equation.
|
| Date: | Tue, 03.05.2016 |
| Time: | 14:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Kleiner Seminarraum der Theor. Physik, 5. Stock, Boltzmanngasse 5 |
| Contact: | H. Steinacker |
| Atomically Precise Nanoscale Contacts
|
| Speaker: | A.B. Shick (Institute of Physics, ASCR, Prague/Czech Republic) |
| Abstract: | The electronic structure of SmB6 and PuB6 was investigated making use of a combination of the density functional theory, and the exact diagonalization (ED) of an effective discrete Anderson impurity model [1]. Intermediate valence ground state with the f-shell occupation n4f =5.6 is found for the Sm atom in SmB6. This ground state is a singlet, and the first excited triplet state ~3 meV higher in the energy. SmB6 is a narrow band insulator already in DFT, with the direct band gap of ~10 meV. The electron correlations increase the band gap, which now becomes indirect supporting the idea of "topological Kondo insulator".
For PuB6, an intermediate valence ground state with the f-shell occupation n5f =5.5 for the Pu atom is calculated. This ground state is a non-magnetic singlet with all angular momenta of the 5f-bath cluster equal to zero. The 5f-shell magnetic moment is completely comp |
| Date: | Tue, 03.05.2016 |
| Time: | 16:00 |
| Location: | Technische Universität Wien, Institut für Angewandte Physik, E134 yellow tower „B“, 5th floor, Sem.R. DB gelb 05 B (room number DB05L03) 1040 Wien, Wiedner Hauptstraße 8-10 |
| Contact: | Ao.Univ.Prof.Dr. Peter Mohn |
| Role of atomic multiplets in intermediate valence SmB6 and PuB6 |
| Speaker: | A.B. Shick (Institute of Physics, ASCR, Prague/Czech Republic) |
| Abstract: | The electronic structure of SmB6 and PuB6 was investigated making use of a
combination of the density functional theory, and the exact diagonalization (ED) of an
effective discrete Anderson impurity model [1]. Intermediate valence ground state with
the f-shell occupation n4f =5.6 is found for the Sm atom in SmB6. This ground state is a
singlet, and the first excited triplet state ~3 meV higher in the energy. SmB6 is a narrow
band insulator already in DFT, with the direct band gap of ~10 meV. The electron
correlations increase the band gap, which now becomes indirect supporting the idea of
"topological Kondo insulator".
For PuB6, an intermediate valence ground state with the f-shell occupation n5f =5.5 for
the Pu atom is calculated. This ground state is a non-magnetic singlet with all angular
momenta of the 5f-bath cluster equal to zero. The 5f-shell magnetic moment is
completely compensa |
| Date: | Tue, 03.05.2016 |
| Time: | 16:00 |
| Location: | Technische Universität Wien, Institut für Angewandte Physik, E134 yellow tower „B“, 5th floor, Sem.R. DB gelb 05 B (room number DB05L03) 1040 Wien, Wiedner Hauptstraße 8-10 |
| Contact: | Ao.Univ.Prof.Dr. Peter Mohn |
| Going beyond leading order in the SMEFT |
| Speaker: | Michael Trott (NBIA Copenhagen) |
| Abstract: | im Rahmen des Teilchenphysikseminars: Model independent EFT approaches to physics beyond the Standard
Model have advanced remarkably in recent years with the emergence
of a coherent formalism - the SMEFT to tackle past and upcoming data.
Developing the SMEFT formalism to include perturbative corrections
can be important in some well measured processes. We will discuss
some of these developments and in particular the calculation of the
process Gamma(h->gamma gamma) beyond tree level in the SMEFT.
|
| Date: | Tue, 03.05.2016 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | A. Hoang, Y. Wang |
|