Versatile operations with calcium and multi-species ion crystals
Auch gedruckt in der BibliothekW: W-H 12.901
FakultätFakultät für Naturwissenschaften
Ressourcen- / MedientypDissertation, Text
Datum der Freischaltung2012-05-07
Coherence effects in a Lambda system of a 40Ca+ ion are investigated. Zeeman sublevels are utilized to evoke electromagnetically induced transparencies. The characteristic dark resonance and line shape alterations are analyzed for varying light field intensities. New features arise by avoiding all coherences in a Lambda-system. This is achieved by exposing the ion to only one single laser light field, going the spectroscopy. Pulsed light sequences ensure stable cooling and spectroscopy. A quantum mechanical description of the process is given, revealing the dark-resonance-free shape of the spectrum. This enables the determination of the Rabi frequency of the applied laser light field as well as the photon collection efficiency of the imaging system. In many cases in QIPC, it is important to precisely determine the position of the ions, for this information obtained from the ions" fluorescence is utilized. The capability of the segmented Paul trap to create custom electric potentials is utilized to form time dependent potentials with multiple trapping wells. The application of feedback control allows purposeful movement of a predefined number of ions and position regulation by altering the trapping voltages. Ion transport over 1 mm with more than 99.8 % success probability is accomplished without any knowledge of the potentials. By means of the feedback control this allows automated dividing of a linear ion crystal into two distinct potentials as well as the opposite process of merging. In order to perform these experiments, several novel techniques for the operation of an ion trap have been developed. A technique for automatic compensation is introduced to minimize the RF driven micromotion of the ion crystal. Additionally, a precise method for simultaneous measuring the oscillation frequencies for individual ions in an ion crystal is presented. Hereby, the oscillation modes of multi-species ion crystals can be analyzed for the determination of dopant isotopes.
LCSHCoherence: Nuclear physics
Quantum information processing