An ¹¹⁵In⁺-¹⁷²Yb⁺ Coulomb crystal clock with 2.5x10^-18 systematic uncertainty

authored by

H. N. Hausser, J. Keller, T. Nordmann, N. M. Bhatt, J. Kiethe, H. Liu, M. von Boehn, J. Rahm, S. Weyers, E. Benkler, B. Lipphardt, S. Doerscher, K. Stahl, J. Klose, C. Lisdat, M. Filzinger, N. Huntemann, E. Peik, T. E. Mehlstäubler

Abstract

We present a scalable mixed-species Coulomb crystal clock based on the ¹S0 ↔ ³P0 transition in ¹¹⁵In+. ¹⁷²Yb+ ions are co-trapped and used for sympathetic cooling. Reproducible interrogation conditions for mixed-species Coulomb crystals are ensured by a conditional preparation sequence with permutation control. We demonstrate clock operation with a 1In⁺-3Yb⁺ crystal, achieving a relative systematic uncertainty of 2.5×10⁻¹⁸ and a relative frequency instability of 1.6×10⁻¹⁵√τ/1s. We report on an absolute frequency measurement with an uncertainty of 1.3×10⁻¹⁶ and optical frequency ratios relative to the ¹⁷¹Yb+ (E3) and ⁸⁷Sr clock transitions with fractional uncertainties of 4.4 and 4.7 parts in 10¹⁸, respectively. The latter are among the most precise measurements of frequency ratios to date and improve upon the previous uncertainty of the ¹¹⁵In+/⁸⁷Sr ratio by two orders of magnitude. We also demonstrate operation with four 115In+ clock ions, which reduces the instability to 9.2×10⁻¹⁶√τ/1s.

Organisation(s)

Institute of Quantum Optics
Laboratory of Nano and Quantum Engineering

External Organisation(s)

National Metrology Institute of Germany (PTB)

Type

Preprint

No. of pages

13

Publication date

26.02.2024

Publication status

E-pub ahead of print

Electronic version(s)

https://doi.org/10.48550/arXiv.2402.16807 (Access: Open)