SNSF Professor of Theoretical Physics

Department of Physics, University of Basel

Klingelbergstrasse 82

4056 Basel, Switzerland

Office 4.30

T +41 (0)61 207 3915 (office)

E-mail: nicolas.sangouard(at)unibas .ch

Research group: http://qotg.physik.unibas.ch

Stephan Weitnauer

Office 1.08B

T +41 (0)61 207 37 18

F +41 (0)61 207 3408

E-mail: stephan.weitnauer(at)unibas.ch

Nicolas Sangouard studied physics at the University of Burgundy in Dijon where he did a PhD in the framework of coherent control. He did a postdoc in quantum optics with M. Fleischhauer in Kaiserslautern in 2005 and also with Nicolas Gisin in Geneva in 2006. In 2007, he obtained a Maitre de Conferences position at the University Paris VII. Returning to Geneva in 2009, he headed the theoretical activities related to quantum optics in Nicolas Gisin's group, while on leave from his permanent position. He received a professorship from the Swiss National Foundation in 2014, which he is using to run an independent research group at the Department of Physics, in the University of Basel.

Our research is focused on quantum optics, i.e. the application of quantum theory to phenomena involving light and its interaction with atomic and mechanical systems. We are interested in quantum networks – networks where nodes are made with atoms and where photons are used to connect the nodes in order to distribute entanglement over the entire network. Beside questions related to the implementation of such networks, we are also interested in protocols for certifying their proper functioning. Of particular interest is the use of Bell tests where the certification can be made device-independently. Quantum networks and device-independent certification in general are expected to provide new applications e.g. for secure long distance communication or for randomness generation. On the fundamental side, one of our goals is to push quantum theory towards unexplored regimes, either to macroscopic masses or to macroscopic photon numbers. This might make it possible to test post quantum theories and more generally, to gain insight into the reasons that make the observation of quantum effects at macroscopic scales difficult. Most of our works are done in close collaboration with leading experimental groups.

- R. Schmied, J.-D. Bancal, B. Allard, M. Fadel, V. Scarani, P. Treutlein, and N. Sangouard,
*Bell correlations in a Bose-Einstein condensate*, Science**352**, 441 (2016). - N. Bruno, A. Martin, P. Sekastki, N. Sangouard, R. Thew, and N. Gisin,
*Displacing entanglement back and forth between the micro and macro domains*, Nature Physics**9**, 545 (2013). - N. Sangouard, C. Simon, H. De Riedmatten, and N. Gisin,
*Quantum repeaters based on atomic ensembles and linear optics*, Rev. Mod. Phys.**83**, 33 (2011). - C. Clausen, I. Usmani, F. Bussieres, N. Sangouard, M. Afzelius, H. De Riedmatten, and N. Gisin,
*Quantum storage of photonic entanglement in a crystal*, Nature**469**, 508 (2011). - N. Gisin, S. Pironio, and N. Sangouard,
*Proposal for implementing device-independent quantum key distribution based on a heralded qubit amplification*, Phys. Rev. Lett.**105**, 070501 (2010).