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

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 J. Phys. fast track paper, preprint arXiv:1510.00223 (2015).

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. See the preprint at arXiv:1508.06461 (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 (2014), see also the news features in Deutschlandfunk and Telebasel.

Two poster prizes for microwave field imaging with atomic vapor cells

Andrew won two poster prizes at the 28th European Frequency and Time Forum in Neuchatel and at the Australian Institute of Physics Congress in Canberra - congratulations! He reported on the application of our microwave field imaging technique to study atom-wall interactions and characterize high-performance vapor cell atomic clocks. The experiments were carried out in collaboration with the Mileti group.

Quantum metrology with a scanning probe atom interferometer

We use a small atomic Bose-Einstein condensate as an interferometric scanning probe to map out a microwave field near a chip surface with a few micrometers resolution. Our interferometer overcomes the standard quantum limit by operating with a many-particle entangled state.
The paper appeared in Phys. Rev. Lett. 111, 143001 (2013).

Earlier news