University of Basel

Previous news from the lab

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).

Microwave field imaging with hot atoms

We have used hot atoms in a vapor cell for imaging of microwave fields near an integrated circuit. Our apparatus is simple and compact and does not require cryogenics or ultra-high vacuum, making this technique interesting for applications.
The paper appeared in Appl. Phys. Lett. 101, 181107 (2012).

Spectroscopy of mechanical dissipation in micro-mechanical membranes

We have measured the frequency dependence of the mechanical quality factor (Q) of SiN membrane oscillators and observed a variation of Q by more than two orders of magnitude. Several distinct resonances in Q were observed that can be explained by coupling to membrane frame modes. [more]
The paper appeared in Applied Physics Letters 99, 143109 (2011).

Realization of an optomechanical interface between atoms and a membrane

We have experimentally realized a hybrid optomechanical system by coupling ultracold atoms to a micromechanical membrane oscillator. We observe both the effect of the membrane vibrations onto the atoms as well as the backaction of the atomic motion onto the membrane. [more]
The paper appeared in Phys. Rev. Lett. 107, 223001 (2011), see also the accompanying Physics Viewpoint.

Quantum state tomography of a spin-squeezed BEC

We have developed a new technique for quantum state tomography on the Bloch sphere and use it to reconstruct the Wigner function of a spin-squeezed Bose-Einstein condensate. [more]
The paper appeared in the New Journal of Physics focus issue on Modern Frontiers of Matter Wave Optics and Interferometry: New J. Phys. 13, 065019 (2011).

Microwave field imaging with ultracold atoms

We have used ultracold atoms for high-resolution imaging of microwave fields near integrated microwave circuits. [more]
The paper appeared on the cover of Applied Physics Letters [APL 97, 051101 (2010)]. For a popular article, see SPS-Communications 33, 10 (2011).