University of Basel

Welcome to the quantum atom optics lab

We belong to the Department of Physics of the University of Basel in Switzerland. Our research focuses on the quantum physics of ultracold atoms and on hybrid quantum systems in which atoms interact with solid-state micro- and nanostructures. The main experimental tool is an "atom chip", which allows us to laser-cool, trap, and coherently manipulate neutral atoms at micrometer distances from a chip surface. [more]

Our research combines quantum-optical with solid-state systems and experiment with theory, employing techniques of laser cooling, Bose-Einstein condensation, micro- and nanofabrication.

Group Picture

News from the lab

Review article on entanglement and quantum metrology with atomic ensembles

Have a look at our new review article on "Non-classical states of atomic ensembles: fundamentals and applications in quantum metrology", a joint work of L. Pezzè, A. Smerzi, M. K. Oberthaler, R. Schmied and P. Treutlein. Comments are welcome at
preprint arXiv:1609.01609 (2016)

Poster prize for quantum networks based on semiconductor quantum dots and atomic ensembles

Janik won a best poster award at the International Conference on Quantum Communication, Measurement and Computing (QCMC) in Singapore - congratulations! He reported progress towards the storage of single quantum dot photons in a rubidium quantum memory. The experiments were carried out in collaboration with the Warburton group.

Bell correlations in a Bose-Einstein condensate

The strongest form of correlations between particles are those that violate a Bell inequality. We have detected such Bell correlations between 480 atoms in a Bose-Einstein condensate, using a witness inequality that we derived in collaboration with the theory groups of N. Sangouard and V. Scarani.
Science 352, 441 (2016), see also the University of Basel press release.

Marie Skłodowska-Curie Fellowship

Dr. Janik Wolters was awarded a Marie-Skłodowska-Curie Fellowship from the European Commission for the project "Cold atom-semiconductor quantum interface" - congratulations! We thank the European Union for the generous support and hope that the project will help to exploit the potential of quantum science to benefit the European economies and societies.

European Research Council (ERC) Starting Grant

The European Research Council has awarded a Starting Grant to Prof. Philipp Treutlein for the project "Modular mechanical-atomic quantum systems", which is scheduled to start in early 2016. We thank the European Union for generously supporting the Swiss research community.
University of Basel press release.

Widefield microwave imaging in alkali vapor cells with sub-100 μm resolution

We record images of microwave fields with sub-100 μm resolution using a microfabricated alkali vapor cell. The setup can additionally image dc magnetic fields, and can be configured to image microwave electric fields. Our technique could prove transformative in the design, characterisation, and debugging of microwave devices and find applications in medical imaging.
New Journal of Physics 17, 112002 (2015), Fast Track Communication.

An artificial Rubidium atom in a semiconductor

In collaboration with the Warburton group, we have developed a semiconductor quantum dot single photon source that emits transform-limited photons at 780 nm, the wavelength of the Rubidium D2 line. The quantum dot photons are tuned into exact resonance with hyperfine transitions of natural Rubidium atoms, a key step towards storing them in an atomic quantum memory.
Phys. Rev. B 92, 245439 (2015).

Sympathetic cooling of a membrane oscillator in a hybrid mechanical-atomic system

We have used ultracold atoms to cool the vibrations of a nanomechanical membrane from room-temperature to 650 mK. While sympathetic cooling with atoms has previously been used to cool other microscopic particles, we extend it to the cooling of an engineered solid-state structure, whose mass is 10 orders of magnitude larger than that of the atoms.
Nature Nanotechnology 10, 55 (2015), see also the news features in Deutschlandfunk and Telebasel.

Earlier news