Observation of Resonant Electric Dipole-Dipole Interactions Between Cold Rydberg Atoms Using Microwave Spectroscopy
MetadataShow full item record
This thesis reports the first observation of the resonant electric dipole-dipole interaction between cold Rydberg atoms using microwave spectroscopy, the observation of the magnetic field suppression of resonant interactions, and the development of a unique technique for precise magnetic field measurements. <br /><br /> A Rydberg state 46<em>d</em><sub>5/2</sub> of laser cooled <sup>85</sup>Rb atoms has been optically excited. A fraction of these atoms has been transferred to another Rydberg state 47<em>p</em><sub>3/2</sub> or 45<em>f</em><sub>5/2,7/2</sub> to introduce resonant electric dipole-dipole interactions. The line broadening of the two-photon 46<em>d</em><sub>5/2</sub>-47<em>d</em><sub>5/2</sub> microwave transition due to the interaction of 46<em>d</em><sub>5/2</sub> with 47<em>p</em><sub>3/2</sub> or 45<em>f</em><sub>5/2,7/2</sub> atoms has been used as a probe of the interatomic interactions. This experiment has been repeated with a DC magnetic field applied. The application of a weak magnetic field (≤0. 6G) has reduced the line broadening due to the resonant electric dipole-dipole interaction, indicating that the interactions are suppressed by the field. Theoretical models have been developed that predict the energy shifts due to the resonant electric dipole-dipole interaction, and the suppression of interactions by magnetic fields. A novel technique for sensitive measurement of magnetic fields using the 34<em>s</em><sub>1/2</sub>-34<em>p</em><sub>1/2</sub> one-photon microwave transition has also been presented. Using this technique, it has been possible to calibrate magnetic fields in the magneto-optical trap (MOT) apparatus to less than 10mG, and put an upper bound of 17mG on any remaining field inhomogeneity.