1. Activity reports on CCTF/CCL JWG on Optical Frequency Metrology
APMP TCL & TCTF
Jakarta;　03 November 2008
Activity reports on CCTF/CCL JWG on Optical Frequency Metrology
Feng-Lei Hong
National Metrology Institute of Japan (NMIJ)
National Institute of Advanced Industrial Science and Technologies (AIST), Japan

2. CCTF/CCL JWG CCL-CCTF Frequency Standards Working Group (from 2007)
CCL: Consultative Committee for Length
　 WG-MeP: Frequency stabilized laser for the definition of the meter.
CCTF: Consultative Committee for Time and Frequency
WG: Secondary representation of the second
CCL-CCTF Frequency
Standards Working Group (from 2007)

3. CCL-CCTF Frequency Standards Working Group
The FSWG is a combined WG caring for the single list of high accuracy frequencies or vacuum wavelengths
Caters for the needs of different communities eg
　　secondary representations of the second, with a view to a future redefinition of the second
　　requirements of the dimensional metrology community in respect of stabilised lasers for the realisation of the metre
　　standards within the infra-red telecommunications region
　　accurate frequencies for fundamental constants and basic physics

4. APMP TCTF/TCL JWG on OFM from 2007
Main subjects of the WG:
a) Optical comb research activities
b) Optical clock research activities
c) Microwave and optical frequency dissemination
d) Optical combs and CCL-K11

5. Members of the JWG Feng-Lei Hong (NMIJ, Coordinator)
Sang Eon Park (KRISS)
Dai-Hyuk Yu (KRISS)
Zhanjun Fang (NIM)
Michael Wouters (NMIA)
Mizuhiko Hosokawa (NICT),
Jing-Long Peng (CMS)

6. Activities
a) Cooperation with ATF to organize a Special Session for Optical Frequency Metrology at ATF2008.
b) Information exchange on optical clocks as “secondary representations of the second”, and optical combs for CCL-K11 including CMCs.

7. Research on optical lattice clocks at APMP
Sr: Tokyo JILA, SYRTE, PTB, LENS, NIM, NICT, NPL
Yb: NIST, NMIJ/AIST, ECNU, KRISS, INRIM, Washington, Wuhan?
Hg: Tokyo, SYRTE

8. Research on ion clocks at APMP
Hg+ & Al+: NIST
Yb+: PTB, NPL
Sr+: NPL, NRC
Ca+: Innsbruck, NICT, Wuhan

9. Research on optical combs at APMP
CMS
KRISS
NIM, ECNU, Peking U., CAS, Wuhan?
NMIA
NICT, NMIJ/AIST

10. Research on optical fiber link for frequency dissemination at APMP
Using optical carrier
NMIJ/AIST
Using MW modulation
NICT, NIM, NMIJ/AIST

11. Science 319, 1808 (2008)