Fiber-coupled single ion as an efficient quantum light source

Understand

We have realized a compact system to efficiently couple the fluorescent light emitted by a single trapped ion to two opposing optical fibers.

• The fibers are tightly integrated in the center electrodes of a miniature endcap trap.
• They capture light from the ion with a numerical aperture of 0.34 each, corresponding to 6% of the solid angle in total.
• The high collection efficiency and high signal-to-background ratio make the setup an ideal quantum light source.