Interfacing light and a single quantum system with a lens.

Abstract

Strong interaction between light and a single quantum system is typically achieved by placing the quantum system in a high finesse cavity. However, the interaction strength provided by focusing light onto the quantum system using a lens might already be sufficient for a number of quantum information processing protocols. Yet, the potential of this simpler and more convenient method is still not fully recognized. In this thesis, we study, experimentally and theoretically, the interaction strength between a quantum system and a focused coherent light field. In particular, we have performed an experiment which directly demonstrated an extinction of more than 10% when we trapped a single Rubidium atom at the focus of a light beam. The results of this experiment are consistent with our theoretical work which predicts the possibility of achieving much stronger interaction by focusing with a lens.