Ultracold 87Rb: from quantum metrology to two-photon ionization

One of the most striking features of quantum mechanics is the prediction that all matter can exhibit wave-like behaviour. Being a fundamental manifestation of the particle wave duality, coherent matter waves can form interference patterns similar to the well-known interference of laser light waves. Bose-Einstein condensates constitute a cloud of bosonic atoms cooled near to absolute zero that form a state of matter described by one wave function - a manifestation of a macroscopic quantum state of matter. Due to the macroscopic wave function and the associated coherence properties, Bose-Einstein condensates are perfect candidates to study the nature of coherence in macroscopic quantum systems. These coherence properties have a wide range of applications and can, on the one hand, be utilised as a tool that, for example, can be applied in high precision measurements. On the other hand, studying the properties of Bose-Einstein condensates themselves is itself an interesting field of research.
This thesis combines both by demonstrating two distinct experiments that tackle each aspect on its own. We present an experiment where, in the future, the Bose-Einstein condensate will be utilised as a probing device for high precision inertial sensing, as well as an experiment, where the coherence properties of a Bose-Einstein condensate after interaction with femtosecond laser pulses are investigated