An Ultraviolet Fiber Fabry–Pérot Cavity for Florescence Collection of Trapped Ions

We demonstrate a fiber Fabry–Pérot cavity in the ultraviolet range, which covers the florescence wavelength for the ^2P_1/2 to ^2S_1/2 transition of Yb^+ and is designed in the bad cavity limit for florescence collection. Benefiting from both the small cavity mode volume and the large atom dipole, a cavity with moderate finesse and high transmission still supports a good cooperativity, which is made and tested in experiment. Based on the measured experimental parameters, simulation performed on the cavity and ion shows a Purcell factor better than 2.5 and a single-mode fiber collection efficiency over 10%. This technology can support ultra-bright single photon sources based on trapped ions and can provide the possibility to link remote atoms as a quantum network.