The Miniature Atomic Clock - Pre-Production Results

Abstract

The authors have developed a Miniature Atomic Clock (MAC) for applications requiring atomic timing accuracy in portable battery-powered applications. Recently, we have completed a pre-production build of 10 devices in order to evaluate unit-to-unit performance variations and to gain statistical confidence in the performance specifications, environmental sensitivity, and manufacturability.

The Chip-Scale Atomic Clock - Recent developments

“…As shown in Figure 11 of [5], the physics packages are capable of supporting STS of 3 5 10 / , while the complete CSACs only demonstrate 2 3 10 / , as shown in Figure 8 of [2]. This 5-6X degradation was, at the time, attributed to additive electronic noise in the interrogation and/or signal recovery processes.…”

“…Comparing Table 1, below, with Table 1 of [2], the majority of the power savings have been realized through improvements in the efficiency of the microprocessor/firmware and the microwave synthesizer. Significant reduction in the required output power from the microwave VCO was accomplished by optimizing the coupling between the synthesizer and the physics package.…”

“…At the 2005 IFCS, we presented our first demonstration of a fully integrated CSAC with power consumption < 200 mW and short-term stability 1 10 / [1]. At the 2007 EFTF/IFCS we reported on the performance consistency of 10 nearlyidentical CSACs, with power consumption of ≈ 125 mW and short-term stability (STS) 2 3 10 / [2].…”

“…In Figure 11 of [2] we presented disturbing results of the frequency "retrace" of the prototype CSACs, i.e. the frequency error measured when the CSAC was periodically powered on and off.…”

Miniature trapped-ion frequency standard with ¹⁷¹Yb⁺

“…Vapor-cell based miniature atomic clocks, such as the CSAC (chip-scale atomic clock) [1,2], have been developed and commercialized over the past decade. Miniature vapor cell clocks, however, suffer from long-term frequency drift mechanisms and therefore can only be used for short-term applications with periodic calibrations.…”