  We present the realization of a combined trapped-ion and optical cavity
system, in which a single Yb^+ ion is confined by a micron-scale ion trap
inside a 230 mum-long optical fiber cavity. We characterize the spatial
ion-cavity coupling and measure the ion-cavity coupling strength using a
cavity-stimulated Lambda-transition. Owing to the small mode volume of the
fiber resonator, the coherent coupling strength between the ion and a single
photon exceeds the natural decay rate of the dipole moment. This system can be
integrated into ion-photon quantum networks and is a step towards cavity
quantum-electrodynamics (cavity-QED) based quantum information processing with
trapped ions.
