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Calendar of Physics Talks Vienna
| Entanglement of two individual neutral atoms using the Rydberg blockade |
| Speaker: | Dr. Tatjana Wilk (Institut d'Optique, Institut d'Optique) |
| Abstract: | The Rydberg blockade is of great interest for many quantum information processing schemes with neutral atoms, since it provides a way to deterministically entangle two or more atoms and to drive fast quantum gates [1]. A major advancement into this direction is the observation of Rydberg blockade between two 87^Rb atoms individually trapped in two neighbouring dipole traps [2]. A laser coupling ground state |g> and Rydberg state |r> of a single atom does not excite both atoms at the same time because the level of the doubly excited state |rr> is detuned from resonance due to the strong interaction between the Rydberg atoms.
The atoms can only absorb a single excitation and are excited into an entangled state (|gr>+|rg>)/sqrt(2). To achieve entanglement between the atoms in their ground states, the Rydberg state is mapped onto another ground state |g'>. The experimental implementation of this scheme and recent results will be discussed [3].
[1] D. Jaksch et al., Phys. Rev. Lett. 85, 2208 (2000). M.D. Lukin et al., Phys. Rev. Lett. 87, 037901 (2001).
[2] E. Urban et al., Nature Phys. 5, 110 (2009). A. Gaëtan et al., Nature Phys. (5, 115 (2009).
[3] T. Wilk et. al, arXiv:0908.0454.
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| Date: | Tue, 15.09.2009 |
| Time: | 10:30 |
| Duration: | 60 min |
| Location: | Ernst-Mach-Hörsaal, Strudlhofgasse 4, 2. Stock. 1090 Wien |
| Contact: | nikolai.kiesel@univie.ac.at |
| Searching for the Rosetta Stone of cosmology: the Stochastic Gravitational-Wave Background |
| Speaker: | Dr. Carlo Nicola Colacino (Dipart.di Fisica (Fakultät für Physik) |
| Abstract: | Vortrag |
| Date: | Thu, 17.09.2009 |
| Time: | 11:00 |
| Duration: | 60 min |
| Location: | Seminarraum B, Währinger Straße 17, 1. Stock |
| Contact: | R. Beig |
| Post-selection technique for quantum channels with applications to quantum cryptography |
| Speaker: | Prof. Dr. Matthias Christandl (Qauntum Information Theory Group LMU München, Deutschland) |
| Date: | Thu, 17.09.2009 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Ernst-Mach-Hörsaal, Strudlhofgasse 4, 2. Stock, 1090 Wien |
| Contact: | Daniela Charlesworth |
| A high-speed QKD system for metropolitan networks |
| Speaker: | Dr. Akisha Tomita (Quantum Computation and Information, I ERATO-SORST, JST, Japan) |
| Abstract: | A high-speed QKD system is being developed under Japanese government's contracted research project for practical QKD systems from 2005 to 2010. Our system is designed to work with 1.25-GHz clock and to generate the final key at 1Mbits/s through a 10-dB-loss fiber (128 kbits/s x 8 waves.)
I will discuss technologies applied to achieve the high speed operation, such as Planar Lightwave Circuit interferometers, WDM clock delivery, and hard-ware key distillation circuit.
If time allows, I will briefly introduce joint QKD network demonstration planed in 2010.
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| Date: | Fri, 18.09.2009 |
| Time: | 14:00 |
| Location: | Ernst-Mach-Hörsaal, Strudlhofgasse 4, 2. Stock, 1190 Wien |
| Contact: | Daniela Charlesworth |
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