TY - JOUR

T1 - Optical frequency ratio of a 171Yb+ single-ion clock and a 87Sr lattice clock

AU - Dörscher, S.

AU - Huntemann, N.

AU - Schwarz, R.

AU - Lange, R.

AU - Benkler, E.

AU - Lipphardt, B.

AU - Sterr, U.

AU - Peik, E.

AU - Lisdat, C.

N1 - Funding information: [ We thank T Legero, D Matei, and S Häfner for operating the Si-2 laser system, C Grebing for operating one of the optical frequency combs during the first few measurements, and N Lemke, S Falke, A Al-Masoudi, M Abdel Hafiz, and C Sanner for their contributions to operating the clocks during some measurements. We acknowledge support by the project 18SIB05 ROCIT, which has received funding from the EMPIR programme co-financed by the Participating States and from the European Union's Horizon 2020 Research and Innovation Programme, and by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy-EXC-2123 QuantumFrontiers-390837967 and CRC 1227 DQ-mat within project B02. We thank T Legero, D Matei, and S Häfner for operating the Si-2 laser system, C Grebing for operating one of the optical frequency combs during the first few measurements, and N Lemke, S Falke, A Al-Masoudi, M Abdel Hafiz, and C Sanner for their contributions to operating the clocks during some measurements. We acknowledge support by the project 18SIB05 ROCIT, which has received funding from the EMPIR programme co-financed by the Participating States and from the European Union’s Horizon 2020 Research and Innovation Programme, and by the Deutsche Forschungs-gemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy—EXC-2123 QuantumFron-tiers—390837967and CRC 1227 DQ-mat within project B02

PY - 2021/2

Y1 - 2021/2

N2 - We report direct measurements of the frequency ratio of the 642 THz 2S1/2(F = 0)-2F7/2(F = 3) electric octupole transition in 171Yb+ and the 429 THz 1S0 -3P0 transition in 87Sr. A series of 107 measurements has been performed at the Physikalisch-Technische Bundesanstalt between December 2012 and October 2019. Long-term variations of the ratio are larger than expected from the individual measurement uncertainties of few 10−17. The cause of these variations remains unknown. Even taking these into account, we find a fractional uncertainty of the frequency ratio of 2.5 × 10−17, which improves upon previous knowledge by one order of magnitude. The average frequency ratio is νYb+ /νSr = 1.495 991 618 544 900 537(38). This represents one of the most accurate measurements between two different atomic species to date.

AB - We report direct measurements of the frequency ratio of the 642 THz 2S1/2(F = 0)-2F7/2(F = 3) electric octupole transition in 171Yb+ and the 429 THz 1S0 -3P0 transition in 87Sr. A series of 107 measurements has been performed at the Physikalisch-Technische Bundesanstalt between December 2012 and October 2019. Long-term variations of the ratio are larger than expected from the individual measurement uncertainties of few 10−17. The cause of these variations remains unknown. Even taking these into account, we find a fractional uncertainty of the frequency ratio of 2.5 × 10−17, which improves upon previous knowledge by one order of magnitude. The average frequency ratio is νYb+ /νSr = 1.495 991 618 544 900 537(38). This represents one of the most accurate measurements between two different atomic species to date.

KW - Frequency ratio

KW - Optical clocks

KW - Strontium lattice clock

KW - Ytterbium ion clock

UR - http://www.scopus.com/inward/record.url?scp=85099239392&partnerID=8YFLogxK

U2 - 10.1088/1681-7575/abc86f

DO - 10.1088/1681-7575/abc86f

M3 - Article

AN - SCOPUS:85099239392

VL - 58

JO - METROLOGIA

JF - METROLOGIA

SN - 0026-1394

IS - 1

M1 - 015005

ER -