Duration: 29 months
Optical atomic clocks can reach fractional inaccuracies below 10^(-18), which enables new applications in fundamental physics, high resolution geodesy (gravity sensing) as well as precision navigation and timing. The central challenge in making these systems portable and flight-ready, however, is in the coherence and scalable delivery of the laser light used to probe the atoms. Integrated photonics are used to partially address this challenge, with optical wave guides improving the relative coherence and pointing stability of light fields. Their use on chip-integrated devices opens up a new path to implementing advanced clock interrogation protocols. These, in turn, enable a reduction in the coherence requirements of the laser sources by better exploiting the underlying atomic systems as reference. We propose to demonstrate this possibility using a twenty-zone surface ion trap array with embedded optical wave guides that deliver all required light fields from the UV to the IR for photo-ionization, Doppler cooling, as well as optical qubit manipulation on the narrow-linewidth transition, enabling ground-state cooling and spectroscopy. Using this (existing) novel device, we will demonstrate the parallel operation of chip-based optical atomic clocks and demonstrate a feed-forward interrogation protocol for improved clock stability. These demonstrations, while being device-specific in their implementation, carry over to the full range of trapped ion and neutral atom frequency standards and provide a first proof-of-concept on a platform that makes full use of integrated photonics for light delivery.
