We report on the alteration of photon-emission properties of a single trapped ion coupled to a high-finesse optical fiber cavity. We show that the vacuum field of the cavity can simultaneously affect the emissions in both the infrared (IR) and ultraviolet (UV) branches of the $\mathrm{\ensuremath{\Lambda}}$-type level system of
40Ca+ despite the cavity coupling only to the IR transition. The cavity induces strong emission in the IR transition through the Purcell effect resulting in a simultaneous suppression of the UV fluorescence. The measured suppression of this fluorescence is as large as 66% compared with the case without the cavity. Through analysis of the measurement results, we have obtained an ion-cavity coupling of ${\overline{g}}_{0}=2\ensuremath{\pi}\ifmmode\times\else\texttimes\fi{}(5.3\ifmmode\pm\else\textpm\fi{}0.1)$ MHz, the largest reported so far for a single ion in the IR domain.
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 μm-long optical fiber cavity. We characterize the spatial ion-cavity coupling and measure the ion-cavity coupling strength using a cavity-stimulated Λ 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 based quantum information processing with trapped ions.