Two-photon gateway and feedback control of a single atom in a cavity

Alexander Kubanek

Published Jan 1, 2010• 0 citations

Abstract

This thesis reports on experiments with single atoms strongly coupled to a single mode of a high-finesse optical cavity. In the first part, it is shown that the motion of the atom in an intracavity dipole trap can be observed with high spatial and temporal resolution. Depending on the atom's current position, the dipole trap is switched to control the motion of the atom. The feedback acts in real time, faster than one oscillation period of the atom in the trap. In the second part the anharmonic energy level structure of the system is investigated. This anharmonicity allows one to selectively populate states containing two energy quanta in a two-photon process, resulting in a nonlinear response of the system with respect to the drive laser intensity. The photon statistics of the light transmitted through the cavity shows photon bunching and super-Poissonian fluctuations, indicating the transmission of photon pairs typical for a two-photon gateway.

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