Cavity-QED with a Single Trapped 40Ca+-Ion.

Radio-frequency ion traps provide ideal conditions for storing and manipulating single particles and localize them with a precision far below their resonance wavelength. By combining an optical cavity with the excellent position control provided by the trap, we have implemented a completely deterministic coupling of ions and the electromagnetic field. In this system we can investigate single-particle cavity QED dynamics with a predefined interaction strength and interaction time, which is not possible in atom-based systems.