Development, Fabrication and Characterisation of Atom Chips

Abstract

Atom chips are robust and extremely powerful toolboxes for quantum optical experiments, since they make it possible to create exceedingly precise magnetic traps for neutral atoms with minimal field modulations. Accurate manipulation of trapped atoms is feasible with magnetic and electric fields created on the atom chip. Therefore atom chips with high quality surfaces and extremely well defined wires were build (roughness < 20nm). Furthermore new generations of atom chips were developed, like the multi-layer atom chip with contact-free wire crossings, the sub-micron structured atom chip and the semiconducting atom chip. Extensive characterisation measurements of atom chip wires demonstrated that the wires stand current densities of up to 10^7A/cm^2 for seconds and voltage differences of more than 500V over 10µm. From the different materials tested doped silicon with a thin silicon dioxide layer is the best qualified substrate for atom chip fabrication. The atom chips fabricated during this thesis have been used in many successful experiments, yielding numerous results. Moreover this thesis established the basics for many further experiments in atom physics and quantum optics and delivers complete instructions for the fabrication of all developed atom chips as well as an introduction to the experiments.