List of atomic clocks

This is a list of some experimental laboratory atomic clocks worldwide.

This list is incomplete; you can help by expanding it.

Image	Name	Location
	CS1, CS2, CSF1, CSF2[1]	Physikalisch-Technische Bundesanstalt Braunschweig, Germany
	FOCS	Federal Institute of Metrology Wabern, Switzerland
	NPL-CsF2, Yb+ and Sr+ ion clocks, Sr lattice clock, 4 hydrogen masers [2][3]	National Physical Laboratory Teddington, London, United Kingdom
	NIST-F1[4], NIST-F2[5]	NIST Boulder Laboratories Boulder, Colorado[6]
	USNO Alternate Master Clock	Schriever Air Force Base El Paso County, Colorado[7]
	WWV	WWVB Larimer County, Colorado[8]
	Department of Defense master clock	United States Naval Observatory Washington, D.C.
	18 cesium atomic clocks and 4 hydrogen maser clocks	National Institute of Information and Communications Technology Koganei, Japan[9]
	Optical lattice clock	University of Tokyo Bunkyō, Tokyo, Japan[10][11]
	NMIJ-F1, NMIJ-F2[12]	National Metrology Institute of Japan Tokyo, Japan
	Optical clock[13]	Hubei, China
	Caesium Beam Atomic Clock[14][15]	Hong Kong Observatory Tsim Sha Tsui, Hong Kong[16]
	9 Agilent 5071A caesium clocks[17]	National Standard Time and Frequency Laboratory Taoyuan, Taiwan[18]
	KRISS-1[19][20]	Korea Research Institute of Standards and Science Daejeon, South Korea
	Caesium atomic clocks[21]	National Metrology Centre Queenstown, Singapore
	NPL clock 1, 2, 3, 4 and 5[22]	National Physical Laboratory of India New Delhi, India
	DOST-PAGASA Juan Time[23]	Department of Science and Technology Taguig, Philippines
	Caesium clocks, Hydrogen Maser [24]	Indonesian Institute of Sciences Jakarta, Indonesia
	SOC: Space Optical Clock breadboard (Sr lattice clock)[25]	European Space Agency Düsseldorf, Germany Braunschweig, Germany Birmingham, United Kingdom Paris, France Florence, Italy Turin, Italy Prague, Czech Republic
	Deep Space Atomic Clock[26]	Jet Propulsion Laboratory La Cañada Flintridge, California
	Caesium atomic clocks[27]	Laboratorium Czasu i Częstotliwości (CBK PAN) Borówiec, Poland

References

1. "Seit wann läuft die erste Atomuhr in der PTB?". Themenrundgänge / Fragen zur Zeit. Physikalisch-Technische Bundesanstalt. Archived from the original on 2012-11-27. Retrieved 2013-02-04.
2. Palmer, Jason. "UK's atomic clock 'is world's most accurate'". BBC. Retrieved 2013-03-02.
3. "Research - Time and Frequency". Retrieved 2015-06-12.
4. "A Brief History of Atomic Clocks at NIST". The National Institute of Standards and Technology (NIST). Retrieved 2013-02-04.
5. "NIST Launches a New U.S. Time Standard: NIST-F2 Atomic Clock". The National Institute of Standards and Technology (NIST). Retrieved 2016-02-09.
6. Newman, Michael E. (1999-12-29). "NIST-F1 Cesium Fountain Clock". NIST News. The National Institute of Standards and Technology (NIST). Retrieved 2013-02-04.
7. "U.S. Naval Observatory Alternate Master Clock". U.S. Navy. Retrieved 2013-02-09.
8. "Larimer County station helps set clocks". Fort Collins Coloradoan. Gannett Company. July 24, 2015. Retrieved August 27, 2018.
9. "Mission of Japan Standard Time Group - Generation of Japan Standard Time (JST)". National Institute of Information and Communications Technology. Retrieved 2013-03-05.
10. Motal, Julius (2011-08-30). "Japanese atomic clock is accurate to a 100 quadrillionth of a second". Geek.com. Ziff Davis, Inc. Retrieved 2013-03-02.
11. "Quantum Metrology Laboratory". RIKEN Advanced Science Institute. Archived from the original on 2013-03-03. Retrieved 2013-03-05.
12. Takamizawa, A.; Yanagimachi, S.; Shirakawa, Y.; Watabe, K.; Hagimoto, K.; Ikegami, T., "Cesium Atomic Fountain Clocks at NMIJ" (PDF), Precise Time and Time Interval Systems and Applications Meeting, pp. 321–328, archived from the original (PDF) on 2011-04-28
13. Wang, Yuanyuan (2012-07-12). "China unveils first optical clock". English News. Xinhuanet. Archived from the original on 2012-07-15. Retrieved 2013-02-04.
14. "Caesium Beam Atomic Clock". The Government of the Hong Kong Special Administrative Region. Retrieved 2013-02-14.
15. "History of Hong Kong Time Service". The Government of the Hong Kong Special Administrative Region. Retrieved 2013-02-11.
16. "Contact us". The Government of the Hong Kong Special Administrative Region. Retrieved 2013-02-11.
17. "Clocks and Time scales". National Time and Frequency Standard Laboratory. Retrieved 2013-02-14.
18. "Current activities of the National Standard Time and Frequency Laboratory of the Telecommunication Laboratories" (PDF). Archived from the original (PDF) on 2013-02-17. Retrieved 2013-02-14.
19. "Development of Korea's First Primary Frequency Standard, 'KRISS-1'" (PDF). KRISS. Retrieved 2013-03-01.
20. Lee, Ho Seong; Kwon, Taeg Yong; Park, Sang Eon; Choi, Sang-Kyung; Park, Young-Ho (August 2004). "Research on Cesium Atomic Clocks at the Korea Research Institute of Standards and Science". Journal of the Korean Physical Society. 45 (2): 256–272. Archived from the original on 2016-03-04. Retrieved 2013-03-06.
21. "About SST". National Metrology Centre. Archived from the original on 2013-04-18. Retrieved 2013-03-01.
22. Shoba, V (2008-12-28). "Why time will stop". The Indian Express. The Indian Express ltd. Retrieved 2013-02-04.
23. "With PST, "Filipino time" is now "on time"". Department of Science and Technology. Retrieved 2014-06-07.
24. "Time Standard". Indonesian Institute of Sciences. Archived from the original on 2016-01-21. Retrieved 2016-06-22.
25. "Space Optical Clock". Institut für Experimentalphysik, Heinrich-Heine-Universität Düsseldorf. Retrieved 2017-01-30.
26. "Deep Space Atomic Clock". NASA's Jet Propulsion Laboratory. NASA. 27 April 2015. Retrieved 2015-10-28.
27. "Uruchomiono najdokładniejszy zegar atomowy w Polsce. Nie straci nawet sekundy przez 200 mln lat". wyborcza.pl. Retrieved 2018-03-24.