Diffraction of a Bose-Einstein Condensate and the Path to an Atom Laser

by Haupert, Fabienne

Abstract (Summary)
In this thesis, we study the diffraction processes of a Bose-Einstein condensate of 87Rb atoms and outline our progress toward the realisation of an atom laser. The experiments are carried out with a condensate that is produced ‘all-optically’; this is covered in the first part of the thesis. For our diffraction processes, we expose the condensate to an intense, pulsed optical standing wave. We perform mean energy measurements and interpret our results with two different theories: one treating the condensed atoms as particles, the other focusing on the atoms’ wave properties. The first interpretation requires knowledge of the theoretical background of the atom-optics -kicked rotor (AOKR); in our experiments, we focus on the resonances in the early-time behaviour of the kicked atoms. The second interpretation retrieves an observation of the temporal Talbot effect—the atomic analogue to the optical Talbot effect. From this point of view, the full resonances represent the integer Talbot effect, whereas the early-time behaviour corresponds to the observation of the fractional Talbot effect. We find for both theoretical interpretations an excellent qualitative agreement between our experimental results and the results of our computer simulation of the AOKR. Furthermore, we outline our future work on the realisation of an atom laser as a tool for coherence measurements of the condensate via atom-counting statistics. In this context, the most current progress in our laboratory is given. We aim for a Bragg-scattering process of our condensate as a modified version of our prospective outcoupling technique for the atom laser; this process is modelled in a semi-classical approach, and our first experimental implementations are presented.
Bibliographical Information:


School:The University of Auckland / Te Whare Wananga o Tamaki Makaurau

School Location:New Zealand

Source Type:Master's Thesis

Keywords:fields of research 240000 physical sciences 240300 atomic and molecular physics nuclear particle plasma


Date of Publication:01/01/2007

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