40Ca+ optical frequency standards with high accuracy

Guan Hua; Huang Yao; Li Cheng-Bin; Gao Ke-Lin

doi:10.7498/aps.67.20180876

Abstract

With the development of the technologies in the lasers and the manipulation of cold atoms, the high precision optical frequency standards have been extensively studied and built in recent years. These high precision frequency standards may play an important role in establishing the new time reference, promoting the researches in the fundamental fields, fulfilling the national strategic needs, etc. In this paper, the research progress of high accuracy 40Ca+ optical frequency standard in Wuhan Institute of Physics and Mathematics (WIPM) of Chinese Academy of Sciences is presented. A new ULE super cavity is adopted for stabilizing the frequency of 729 nm clock laser, and the stability of the laser is improved now to 2×10-15 in a duration of 1-100 s. By controlling the external fields and other environmental influences, especially suppressing the micromotion effects of the trapped ion, the uncertainty of the optical frequency standard based on a single 40Ca+ is reduced to 5.5×10-17. The stability of 5×10-17 in a duration of 20000 s is achieved via the comparison between two 40Ca+ optical frequency standards. Several precision measurement experiments are performed, based on the high precision 40Ca+ optical frequency standard. The absolute value of the clock transition frequency of the 40Ca+ optical frequency standard is measured second time, using an optical comb referenced to a hydrogen maser which is calibrated via GPS referenced to UTC (NIM)) using the precise point positioning data-processing technique. The frequency offset of UTC (NIM) relative to the SI second can be evaluated through BIPM circular-T reports, and the newly measured value of m 4s 2S1/2-3m d 2D5/2 transition is adopted by CCTF-20, thus updating the recommended value of 40Ca+ optical clock transition. Besides the absolute frequency measurement, the magic wavelengths of 40Ca+ optical clock transition are measured precisely, and this work is a milestone for establishing all-optical trapped-ion clocks. The lifetime of the m 3 d 2D3/2 and m 3 d 2D5/2 state in 40Ca+ are precisely measured, too. The work mentioned above contributes to the researches of the precision measurements based on cold atomic systems.

Keywords:

Authors and contacts

1.
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China;
2.
Key Laboratory of Atomic Frequency Standards, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China;
3.
Center for Cold Atom Physics, Chinese Academy of Sciences, Wuhan 430071, China

Corresponding author: Gao Ke-Lin, klgao@wipm.ac.cn

Funds: Project supported by the National Natural Science Foundation of China (Grant Nos. 91336211, 11474318, 11622434, 11774388), the National Basic Research Program of China (Grants Nos. 2005CB724502, 2012CB821301), and the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB21030100).

References

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[32]	Huang Y, Liu Q, Cao J, Ou B, Liu P, Guan H, Huang X, Gao K 2011 Phys. Rev. A 84 053841
[33]	Huang Y, Cao J, Liu P, Liang K, Ou B, Guan H, Huang X, Li T, Gao K 2012 Phys. Rev. A 85 030503
[34]	Bian W, Huang Y, Guan H, Liu P, Ma L, Gao K 2016 Rev. Sci. Instrum. 87 063121
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[36]	Shao H, Huang Y, Guan H, Qian Y, Gao K 2016 Phys. Rev. A 94 042507
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[41]	Guan H, Guo B, Huang G, Shu H, Huang X, Gao K 2007 Opt. Commun. 274 182
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Cited By

[1]	Bergquist J C, Jefferts S R, Wineland D J 2001 Phys. Today 54 37
[2]	Rosenband T, Hume D B, Schmidt P O, Chou C W, Brusch A, Lorini L, Oskay W H, Drullinger R E, Fortier T M, Stalnaker J E, Diddams S A, Swann W C, Newbury N R, Itano W M, Wineland D J, Bergquist J C 2008 Science 319 1808
[3]	Margolis H, Barwood G P, Huang G, Klein H A, Lea S N, Szymaniec K, Gill P 2004 Science 306 1355
[4]	Madej A A, Dubé P, Zhou Z, Bernard J E, Gertsvolf M 2012 Phys. Rev. Lett. 109 203002
[5]	Huntemann N, Okhapkin M, Lipphardt B, Weyers S, Tamm C, Peik E 2012 Phys. Rev. Lett. 108 090801
[6]	Chou C W, Hume D B, Koelemeij J C J, Wineland D J, Rosenband T 2010 Phys. Rev. Lett. 104 070802
[7]	Chwalla M, Benhelm J, Kim K, Kirchmair G, Monz T, Riebe M, Schindler P, Villar A S, Hansel W, Roos C F, Blatt R, Abgrall M, Santarelli G, Rovera G D, Laurent Ph. 2009 Phys. Rev. Lett. 102 023002
[8]	Huntemann N, Sanner C, Lipphardt B, Tamm C, Peik E 2016 Phys. Rev. Lett. 116 063001
[9]	Takamoto M, Hong F, Higashi R, Katori H 2005 Nature 435 321
[10]	Ludlow A D, Zelevinsky T, Campbell G K, Blatt S, Boyd M M, de Miranda M H G, Martin M J, Thomsen J W, Foreman S M, Ye J, Fortier T M, Stalnaker J E, Diddams S A, le Coq Y, Barber Z W, Poli N, Lemke N D, Beck K M, Oates C W, Hinkley N 2008 Science 319 1805
[11]	Hinkley N, Sherman J A, Phillips N B, Schioppo M, Lemke N D, Beloy K, Pizzocaro M, Oates C W, Ludlow A D 2013 Science 341 1215
[12]	McFerran J, Yi L, Mejri S, Manno S, Zhang W, Guéna J, le Coq Y, Bize S 2012 Phys. Rev. Lett. 108 183004
[13]	Nicholson T L, Campbell S L, Hutson R B, Marti G E, Bloom B J, McNally R L, Zhang W, Barrett M D, Safronova M S, Strouse G F, Tew W L, Ye J 2015 Nat. Commun. 6 6896
[14]	Campbell S L, Hutson R B, Marti G E, Goban A, Darkwah Oppong N, McNally R L, Sonderhouse L, Robinson J M, Zhang W, Bloom B J, Ye J 2017 Science 358 90
[15]	Ushijima I, Takamoto M, Das M, Ohkubo T, Katori H 2015 Nat. Photon. 9 185
[16]	Schioppo M, Brown R C, McGrew W F, Hinkley N, Fasano R J, Beloy K, Yoon T H, Milani G, Nicolodi D, Sherman J A, Phillips N B, Oates C W, Ludlow A D 2016 Nat. Photon. 11 48
[17]	Huang Y, Guan H, Liu P, Bian W, Ma L, Liang K, Li T, Gao K 2016 Phys. Rev. Lett. 116 013001
[18]	Lin Y, Wang Q, Li Y, Meng F, Lin B, Zang E, Sun Z, Fang F, Li T, Fang Z 2015 Chin. Phys. Lett. 32 090601
[19]	Zhang X, Zhou M, Chen N, Gao Q, Han C, Yao Y, Xu P, Li S, Xu Y, Jiang Y, Bi Z, Ma L, Xu X 2015 Laser Phys. Lett. 12 025501
[20]	Liu H, Zhang X, Jiang K, Wang J, Zhu Q, Xiong Z, He L, Lyu B 2017 Chin. Phys. Lett. 34 020601
[21]	Wang Y, Yin M, Ren J, Xu Q, Lu B, Han J, Guo Y, Chang H 2018 Chin. Phys. B 27 023701
[22]	Che H, Deng K, Xu Z, Yuan W, Zhang J, Lu Z 2017 Phys. Rev. A 96 013417
[23]	Shang J, Cui K, Cao J, Wang S, Chao S, Shu H, Huang X 2016 Chin. Phys. Lett. 33 103701
[24]	Zou H, Wu Y, Chen G, Shen Y, Liu Q 2015 Chin. Phys. Lett. 32 054207
[25]	Fu X, Fang S, Zhao R, Zhang Y, Huang J, Sun J, Xu Z, Wang Y 2018 Chin. Opt. Lett. (Accepted)
[26]	Shi T, Pan D, Chang P, Shang H, Chen J 2018 Rev. Sci. Instrum. 89 043102
[27]	Champenois C, Houssin M, Lisowski C, Knoop M, Hagel G, Vedel M, Vedel F 2004 Phys. Lett. A 331 298
[28]	Matsubara K, Hachisu H, Li Y, Nagano S, Locke C, Nogami A, Kajita M, Hayasaka K, Ido T, Hosokawa M 2012 Opt. Express 20 22034
[29]	Shu H, Guan H, Huang X, Li J, Gao K 2005 Chin. Phys. Lett. 22 1641
[30]	Drever R W P, Hall J L, Kowalski F V, Hough J, Ford G M, Munley A J, Ward H 1983 Appl. Phys. B 31 97
[31]	Guan H, Liu Q, Huang Y, Guo B, Qu W, Cao J, Huang G, Huang X, Gao K 2011 Opt. Commun. 284 217
[32]	Huang Y, Liu Q, Cao J, Ou B, Liu P, Guan H, Huang X, Gao K 2011 Phys. Rev. A 84 053841
[33]	Huang Y, Cao J, Liu P, Liang K, Ou B, Guan H, Huang X, Li T, Gao K 2012 Phys. Rev. A 85 030503
[34]	Bian W, Huang Y, Guan H, Liu P, Ma L, Gao K 2016 Rev. Sci. Instrum. 87 063121
[35]	Liu P, Huang Y, Bian W, Shao H, Guan H, Tang Y, Li C, Mitroy J, Gao K 2015 Phys. Rev. Lett. 114 223001
[36]	Shao H, Huang Y, Guan H, Qian Y, Gao K 2016 Phys. Rev. A 94 042507
[37]	Guan H, Shao H, Qian Y, Huang Y, Liu P, Bian W, Li C, Sahoo B K, Gao K 2015 Phys. Rev. A 91 022511
[38]	Shao H, Huang Y, Guan H, Li C, Shi T, Gao K 2017 Phys. Rev. A 95 053415
[39]	Barton P A, Donald C J S, Lucas D M, Stevens D A, Steane A M, Stacey D N 2000 Phys. Rev. A 62 032503
[40]	Kreuter A, Becher C, Lancaster G P T, Mundt A B, Russo C, Häffner H, Roos C, Hänsel W, Schmidt-Kaler F, Blatt R 2005 Phys. Rev. A 71 032504
[41]	Guan H, Guo B, Huang G, Shu H, Huang X, Gao K 2007 Opt. Commun. 274 182
[42]	Qu W C, Huang Y, Guan H, Huang X R, Gao K L 2011 Chin. J. Lasers 38 0803008 (in Chinese) [屈万成, 黄垚, 管桦, 黄学人, 高克林 2011 中国激光 38 0803008]
[43]	Bureau International des Poids et Mesures (BIPM), Consultative Committee for Time and Frequency (CCTF) Report of the 20th Meeting (September 17-18, 2015) to the International Committee for Weights and Measures https://www.bipm.org/utils/common/pdf/CC/CCTF/CCTF20.pdf
[44]	Tang Y, Qiao H, Shi T, Mitroy J 2013 Phys. Rev. A 87 042517

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