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Calendar of Physics Talks Vienna
| Speaker: | Leo Kouwenhoven (Kavli Institute of Nanoscience, Faculty of Applied Sciences, Delft University of Technology, Netherlands) |
| Abstract: | We use quantum dot structures in various solid state systems to realize controllable two-level quantum systems. We focus on spin states, either one electron doublet states (i.e. spin-up or spin-down) or two-electron singlet and triplet states. Using time-varying magnetic and electric fields we are able to manipulate the spin states, create quantum superpositions and measure individual spins.
The material systems include GaAs/AlGaAs semiconductor heterostructures, semiconducting nanowires and carbon nanotubes. These materials have their own advantages that can be employed to engineer a spin-friendly environment. These include fabrication and electrical-control issues as well as the strength of the hyperfine interaction (i.e. presence or absence of nuclear spins) and the spin-orbit interaction.
We are also investigating the feasibility of transferring local spin-qubit states into flying-qubit photon states for which we develop nanoscale quantum-LED's. Two-electron entanglement is studied by using superconducting materials as electronic leads.
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| Date: | Mon, 19.11.2007 |
| Time: | 17:00 |
| Location: | Technische Universität Wien, Freihaus, |
| Contact: | J. Schmiedmayer |
| Progress in chiral perturbation theory |
| Speaker: | Gerhard Ecker (Univ. Wien) (Fakultät für Physik) |
| Abstract: | im Rahmen des Teilchenphysikseminars |
| Date: | Tue, 20.11.2007 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Großer Seminarraum, Boltzmanngasse 5, 5. Stock |
| Contact: | W. Grimus, H. Neufeld |
| Nonperturbative aspects of noncommutative gauge theory |
| Speaker: | Richard Szabo (Edinburgh) |
| Date: | Tue, 20.11.2007 |
| Time: | 17:00 |
| Location: | ESI Schrödinger Lecture Hall |
| Contact: | secr@esi.ac.at |
| The classical Standard model and noncommutative Geometry |
| Speaker: | John Barrett (Nottingham) |
| Date: | Wed, 21.11.2007 |
| Time: | 15:30 |
| Location: | ESI Schrödinger Lecture Hall |
| Contact: | secr@esi.ac.at |
| Nonperturbative aspects of noncommutative gauge theory |
| Speaker: | Richard Szabo (Edinburgh) |
| Date: | Wed, 21.11.2007 |
| Time: | 17:00 |
| Location: | ESI Schrödinger Lecture Hall |
| Contact: | secr@esi.ac.at |
| Nonperturbative aspects of noncommutative gauge theory |
| Speaker: | Richard Szabo (Edinburgh) |
| Date: | Thu, 22.11.2007 |
| Time: | 17:00 |
| Location: | ESI Schrödinger Lecture Hall |
| Contact: | secr@esi.ac.at |
| Some quantum-gas physics beyond Gross-Pitaevskii |
| Speaker: | Dr. Ofir Alon (Universität Heidelberg) |
| Abstract: | The necessity to go beyond the popular Gross-Pitaevskii theory to properly
describe strongly-interacting cold bosonic atoms, and even weakly-interacting
atoms in double- and multi-well traps has by now become well-accepted by the
community. Starting with a system of attractive condensates on a ring and
ending with that of repulsive bosons in general traps, we present new
theoretical and computational approaches going beyond standard mean-field.
These have enabled us to predict new physical phenomena. I discuss
fragmentation of attractive and repulsive condensates; a zoo of
Mott-insulator phases in optical lattices [thereby going beyond the
popular Bose-Hubbard model]; demixing scenarios of bosonic mixtures in
optical lattices on various length scales; the pathway to fermionization
of trapped cold bosonic systems; interferences in the density of two
condensates consisting of identical or different atoms;
and how to split a Bose-Einstein condensate. |
| Date: | Fri, 23.11.2007 |
| Time: | 10:30 |
| Duration: | 50 min |
| Location: | Instut f. Photonik, TU Wien, Gusshausstrasse 27, Seminarraum CBEG02 |
| Contact: | Armin Scrinzi |
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