The application of micro-structured optical elements to create compact and robust experiments in atom optics is an exceedingly appealing approach in today's research in the field of quantum optics. In this process, the manipulation of the internal and external degrees of freedom of neutral atoms in magnetic and optical micropotentials is of particular interest. These studies are motivated by applications in quantum information processing as well as the possibility to develop compact atom interferometers with high precision. The controlled transport and guiding of ensembles of atoms in magnetic and optical potentials and consequently the coherence of the internal states is of importance. In this thesis, a system is investigated in which neutral 85Rb atoms are trapped in a two-dimensional array of dipole traps. The traps are formed by homogeneously illuminating a micro-lens array with a single collimated laser beam. Atoms trapped in the focal plane of the array can be transported by changing the incident angle of the laser beam. In this way, a transport distance of a full trap separation (54µm) can be achieved. The precision in approaching defined position is smaller then 10nm. With transport times of 2ms neither a heating of the ensemble of atoms nor a loss of atoms is observed. To transport atoms over larger distances, a shift register is demonstrated, which is based on a consecutive transport and reloading of two independent dipole trap arrays. In addition to controlling the external degrees of freedom, it is possible to induce arbitrary coherent superpositions of the hyperfine splitting of the groundstate by using a Raman laser system. The coherence of the internal superpositions is investigated using Ramsey and echo sequences. The Ramsey measurements reveal an inhomogeneous dephasing with a time constant T2*=3,8ms, which relates to the finite temperature of the atoms in the dipole traps. This effect is reversible by extending the sequence to an echo measurement. Thus, it is possible to determine the coherence time of the superposition, which is T2'=74ms. An analysis of the effects limiting the coherence leads to homogeneous dephasing. The loss in contrast is due to heating effects induced by the dipole trap laser. The transport does not affect the coherence time (T2'=71ms), though a constant and reproducible phase shift of <Pi/11 was observed. In the second part of this thesis, a novel micro-optical ringlens is presented. With this it is possible to create a circular dipole trap with a diameter of 1,5mm. After loading the atoms into the ring structure, a free as well as an accelerated circular movement of the ensemble of atoms was demonstrated. By partially illuminating the ring lens with an elongated gaussian laser beam, a controlled guiding of atoms inside the ring can be realized. A lossless and variable splitting of the atomic cloud inside the ring expands this procedure to a closed interferometer structure for future measurements in atom interferometry. | English |