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Coherent control of high–quality factor optical transitions in atoms has revolutionized precision frequency metrology. Leading optical atomic clocks rely on the interrogation of such transitions in either single ions or ensembles of neutral atoms to stabilize a laser frequency at high precision and accuracy. We demonstrate a platform that combines the key strengths of these two approaches, based on arrays of individual strontium atoms held within optical tweezers. We report coherence times of 3.4 seconds, single-ensemble duty cycles up to 96% through repeated interrogation, and frequency stability of 4.7 × 10 −16 (τ/s) –1/2 . These results establish optical tweezer arrays as a powerful tool for coherent control of optical transitions for metrology and quantum information science.
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An optical atomic clock using 4DJ states of rubidium
We analyze an optical atomic clock using two-photon 5S1/2-4DJ transitions in rubidium. Four one- and two-color excitation schemes to probe the 4D3/2 and 4D5/2 fine-structure states are considered in detail. We compare key characteristics of Rb 4DJ and 5D5/2 two-photon clocks. The 4DJ clock features a high signal-to-noise ratio due to two-photon decay at favorable wavelengths, low dc electric and magnetic susceptibilities, and minimal black-body shifts. Ac Stark shifts from the clock interrogation lasers are compensated by two-color Rabi-frequency matching. We identify a ‘magic’ wavelength near 1060 nm, which allows for in-trap, Doppler-free clock-transition interrogation with lattice-trapped cold atoms. From our analysis of clock statistics and systematics, we project a quantum-noise-limited relative clock stability at the 10−13 τ (s)-level, with integration time τ in seconds, and a relative accuracy of ∼10−13/sqrt(t(s)). We describe a potential architecture for implementing the proposed clock using a single telecom clock laser at 1550 nm, which is conducive to optical communication and long-distance clock comparisons. Our work could be of interest in efforts to realize small and portable Rb clocks and in high-precision measurements of atomic properties of Rb 4DJ-states.
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- Award ID(s):
- 2110049
- PAR ID:
- 10627802
- Publisher / Repository:
- IOP
- Date Published:
- Journal Name:
- Quantum Science and Technology
- Volume:
- 9
- Issue:
- 4
- ISSN:
- 2058-9565
- Page Range / eLocation ID:
- 045046
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1088/2058-9565/ad77ef
