Hyperpolarizability and Operational Magic Wavelength in an Optical Lattice Clock
Open accessAbstract
Optical clocks benefit from tight atomic confinement enabling extended interrogation times as well as Doppler- and recoil-free operation. However, these benefits come at the cost of frequency shifts that, if not properly controlled, may degrade clock accuracy. Numerous theoretical studies have predicted optical lattice clock frequency shifts that scale nonlinearly with trap depth. To experimentally observe and constrain these shifts in an ^{171}Yb optical lattice clock, we construct a lattice enhancement cavity that exaggerates the light shifts. We observe an atomic temperature that is proportional to the optical trap depth, fundamentally altering the scaling of trap-induced light shifts and simplifying their parametrization. We identify an "operational" magic wavelength where frequency shifts are insensitive to changes in trap depth. These measurements and scaling analysis constitute an essential systematic characterization for clock operation at the 10^{-18} level and beyond.
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The thermal shields facilitate characterisation of Stark effects from blackbody radiation and provide an in-situ Faraday enclosure shielding the atoms from static electric fields.
“This facilitates characterisation of a key systematic effect afflicting optical clocks, Stark effects from blackbody radiation bathing the ultracold atoms, and further provides an insitu Faraday enclosure shielding the atoms from static electric fields due to stray charges on the vacuum apparatus 24 .”
From Atomic clock performance enabling geodesy below the centimetre level (2018) · cites this paper as [24]
The Stark shift due to stray electric fields is consistent with zero at better than the 10^-19 level on both systems.
“By applying voltage to the windows of the thermal shield, the Stark shift due to stray electric fields is found to be consistent with zero at better than the 10 -19 level on both systems 24 .”
From Atomic clock performance enabling geodesy below the centimetre level (2018) · cites this paper as [24]
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Self-citation
- Authors
- Brown, R. C., Phillips, N. B., Beloy, K., McGrew, W. F., Schioppo, M., Fasano, R. J., Milani, G., Zhang, X., Hinkley, N., Leopardi, H., Yoon, T. H., Nicolodi, D., Fortier, T. M., & Ludlow, A. D.
- Affiliations
- National Institute of Standards and Technology (US)
- ORCID
- Venue
- Physical Review Letters
- Publisher
- American Physical Society (APS)
- Published
- 2017-12-19
- Volume
- 119
- Issue
- 25
- Pages
- 253001-253001
- ISSN
- 0031-9007 (ISSN-L)
- 1079-7114
- OpenAlex
- W2743882218
- Cited by
- 101
- References
- 55
- Citations by year
- 2026: 5 · 2025: 16 · 2024: 14 · 2023: 11 · 2022: 12 · 2021: 8 · 2020: 9 · 2019: 9 · 2018: 16 · 2017: 1
- FWCI
- 4.70
- Type
- journal article
- Language
- en
- Open access
- green
- arxiv.org
- Licence
- Locations
- Physical Review Letters (publishedVersion)
- PubMed (publishedVersion)
- arXiv (Cornell University) (submittedVersion)
- PORTO@Iris (submittedVersion, other-oa)
- PORTO Publications Open Repository TOrino (Politecnico di Torino) (submittedVersion, other-oa)
- arXiv (Cornell University)
- Bulletin of the American Physical Society
- Funders
- National Aeronautics and Space Administration
- Defense Advanced Research Projects Agency
- National Academy of Sciences
- Topics
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Advanced Frequency and Time Standards
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Cold Atom Physics and Bose-Einstein Condensates
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Atomic and Subatomic Physics Research
- Keywords
- optical lattice clock, hyperpolarizability, 171Yb, atomic temperature, systematic frequency shifts, clock accuracy
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