In these projects, we investigate the coupling of ultracold atoms to the vibrations of micro- and nanoscale mechanical oscillators. As a first experimental step we have used a BEC to read out the vibrations of a microcantilever. A goal is to build hybrid quantum systems in which the atoms are used to cool, read out, and coherently manipulate the oscillators' state. [more]

In this experiment we use microwave near-fields on an atom chip to generate potentials which depend on the atomic internal state. We observe coherent dynamics of BECs in such potentials and perform trapped-atom interferometry. Atomic collisions in the potential are used to prepare spin-squeezed and many-particle entangled states. This technique is also very promising for the implementation of chip-based quantum gates. [more]

As a first application of atom chips, we have realized an atomic clock in a chip trap. We have shown that coherence of atomic superposition states can be maintained for seconds at micrometer distance from the room-temperature chip surface. This is crucial for applications of atom chips in quantum information processing and precision measurement. [more]