Miniature Trapped-Ion Frequency Standard with Yb

We describe the development and frequency instability measurements of a highly miniaturized, buffer gas cooled, trapped-ion atomic clock. The clock utilizes the 12.6 GHz hyperfine transition of the Yb ion. A custom-built 3 cm vacuum package containing the ion trap is integrated with other key elements of the atomic frequency standard, including a photo multiplier tube, miniaturized laser sources at 369 nm and 935 nm, a local oscillator, and control electronics. With the clock physics package assembled on a 10 cm x 15 cm breadboard, the long-term fractional frequency instability was measured to be 6 × 10 at 25 days of integration. Later, the clock physics package was further miniaturized, and the frequency instability was measured to be 2 × 10/τ at integration times up to 10,000 s. Keywords—atomic clock; trapped ions;