Activity report from NICT

Transcription

1 Activity report from NICT APMP 2016 / TCTF meeting November, 2016 National Institute of Information and Communications Technology (NICT) Japan 1 1

2 Space time standards laboratory Atomic Frequency Standards G Precise Atomic clocks development Opt. clock VLBI Space-Time Measurement G VLBI technique for precise T&F transfer Generation, Measurement, and dissemination of the T&F standard Time and Frequency transfer G T&F transfer Techniques by using the optical fibers, satellites, and wireless TWSTFT GNSS THz Std. Opt. comb Japan Standard Time G Cs primary CSAC Generation and Dissemination Of Japan Standard Time Opt. fiber Wireless 2

3 Space time standards laboratory Atomic Frequency Standards G RM: T. Ido H. Ishijima, S. Itoh Sr opt. lattice H. Hachisu Space-Time Measurement G 34m Antenna Super wideband Feed RM: M. Sekido M. Tsutsumi T. Kondo Analysis software E. Kawai H. Ujihara K. Takefuji Space time standards lab. In + ion-trap Director: Y. Hanado (K. Hayasaka) N. Ohtsubo H. Nezu (M. Hosokawa) Y. Li (Technical Expert) (Y. Koyama) THz S. Nagano Japan Standard Time G M. Kajita RM: K. Imamura M: H. Saito Cs primary H. Narita, M. Mizuno H. Usui M. Kumagai Timescale LF station TelJJY, NTP, CSAC Calib. Service F. Nakagawa K. Matsubara M. Hara H. Ito S. Tsuchiya (A. Machizawa) Y. Yano N. Kotake Time and Frequency transfer G RM: R. Ichikawa M. Aida R. Tabuchi GNSS T. Gotoh H. Takiguchi TWSTFT M. Fujieda Wireless 2way N. Shiga T. Yasuda B. Panta 3

4 Timescale JST : Time scale generation Clocks for generating UTC(NICT) : Cs 5071A : 18 (ensemble timescale) Anritsu H Masers : 1(source) + 2(backup) The behavior of UTC(NICT) : UTC UTC(NICT) < 20 ns. stability ~ 5x10 2x10 UTC UTC(NICT) (ns) Adj. freq. to trce UTC ( x 1E-15) Allan deviation (log scale) Cs ensemble timescale H-maser -15 UTC(NICT) Year Averaging time (sec) 4

5 JST : Time scale generation Distributed system for Japan Standard Time generation Features NET from all distributed clocks linked via satellites Multiple generation of NET by common database at remote sites (NET: NICT Cs Ensemble Timescale) 現在の状況 Sub-station at Kobe Timescalegeneration sub system system including atomic clocks and time link systems have been installed and calibrated. Preliminary i operation tests t are in progress. 5

6 JST : Dissemination and Calibration LF stations LF40 : 1999 ~ LF60 : 2001 ~ System renewed (FY2012 FY2015) hagane-yama station 60kHz 23kW Telephone JJY Access > /month. Accesses are increasing. Ohtakadoya -yama station 40kHz 13kW Time stamping service ISO /IEC :2015 Calibration service Peer review (2016 Mar) 1,5,10M On site : 28 Remote: 2 ( ) 2016 FPGA based NTP server can accept up to 1 million requests / sec. Public NTP Upcoming Leap second ( ) Accesses > 2 billion / day. (Oct. 2016) (July 1, 2015) 6

7 GNSS time link Satellite T&F Transfer International time link For domestic link 3 receivers : Semi realtime Common view 2 : Septentrio PolaRX was developed for the link of 1 : Dicom GTR50 NICTHQ Kobe, two LF stations. TWSTFT Calibrated by BIPM G1 trip (Apr. 2016) Regular time link Asia and Domestic : Eutelsat 172A Asia EU : AM 2 Asia Hawaii US : Eutelsat 172A * The systems at Hawaii will be terminated at the end of March * Ai Asia USNO observation has stopped since August New system New TWSTFT modem is under development. 7

8 Time transfer facilities at Koganei-HQ 8

9 T&F Transfer : VLBI VLBI for T&F transfer Quasar (Radio object) (common radio source) Broadband VLBI system Super wideband ( GHz) Broadband Feed & High speed Sampler 13m antenna(gsi) 34m antenna(nict) (Very Long Baseline Interferometry) Testing performamce of Freq. comparison. 1.6m-2.4m antenna 0.3ps@1s precision NMIJ NICT Routine observation signal path has become ready. Testing performance with 5 11GHz Observations. Clock Comparion with VLBI and GPS 9

10 T&F Transfer : ACES Join to ACES mission by ESA ACES (Atomic clock ensemble in space) Laser cooled Cs atomic clock & Active H maser in ISS. Launch in 2018, operation for 3yrs. NICT/NMIJ/Univ. Tokyo will join to ACES for a global link of optical clocks. One of 7 MW Ground Terminals will be settled at NICT (delegate of Japan). Platform for the MWL GT was completed on the rooftop of the NICT HQ building. ACES MWL GT Ground Station NICT Google map UT NMIJ Developing optical clocks Univ.Tokyo: Sr, Hg NICT: Sr, Ca+ NMIJ: Yb, Sr 10

11 Atomic clocks and Advanced techniques Microwave clocks Cs Fountain THz standard THz comb Chip Scale Atomic Clock (CSAC) Newly started since 2016 NICT CsF1 NICT CsF2 (2006~) (under development) z Optical clocks r U Ultrastable laser In + /Ca + Ion trap Sr Optical lattice Optical comb 11

12 Optical clocks In + ion with two Ca + as coolant Sr optical lattice Detection? 159nm 204MHz 1 P 1 3 P 1 In operation detection 3 P 0 230nm 360kHz clock transition =237 nm =0.20 s 1 0.8Hz S 0 Lamb Dicke confinement confirmed by observing the sidebands Quantum jump observed by the state detection using the 1 S 0-3 P 1 Frequency measurement as well as evaluation of the systematics are ongoing. since 2011 Uncertainty in 2015 was further reduced by removing dc stray charge. Link uncertainty between TAI and SI second reduced by using five-day mean of TAI frequency, allowing absolute frequency measurements with uncertainty below (Hz z) Sr CCTF2015 SYRTE PTB NICT NMIJ NIM this work 12

13 Optically steered time scale HM Phase micro stepper (PMS) T_Sr An optical lattice clock estimates linear drift rate of the HM in short time Operation once in a week for 10 4 s is sufficient Frac ctional freq quency (x ) Sr 4 months HM frequency calibrated by an 10 4 s operation of optical clock Tim me (ns) Apr UTC-HM(Sr steered) UTC-UTC(NICT) UTC-PFS -2 MJD May Jun. MJD Difference from the time scale of the SI-second < 3 ns maintained during a half year 13

14 Generation of THz cw signal THz frequency standard Tunable THz-CW synthesizer Using 2 lasers coupled into UTC PD. CW radiation : THz. THz freq, measurement system THz counter based on THz comb precision: 1 x THz THz comb application THz > > MW synthesizer THz < > Optical synthesizer THz reference frequency transfer via optical fiber Method-1 : based on the technique of Tunable synthesizer Method-2 : based on THz-comb & THz Opt. synthesizer 4 x precision at 0.3THz was demonstrated. 14

15 MRA related activities GNSS calibration Condition of NICT System BIPM calibration was April NIM NICT calibration is ongoing. (thanks to the TC Initiative ) We are verifying the calibration procedure and making a manual. MEDEA workshop (26-30 September, 2016) Dr. Ichikawa gave a lecture. MRA activities On-site Peer March, 2016 => approval from NITE (ISO/IEC 17025) GNSS calibrator for G2 trips Renewed CMC (registered on KCDB in Oct. 2016) New menus: Time scale difference ( 0.5~0.5s), Frequency (1~100MHz) 15

16 Summary of topics Japan Standard Time and MRA: Kobe sub station: preliminary operation tests are ongoing. LF stations: System renewals at both stations finished in MRA: On site peer was Mar. 2016, new CMC was registered Oct T&F transfer: GNSS: BIPM calib. was Apr. 2016, NIM NICT calib. is ongoing. TWSTFT: Hawaii station will be terminated in Mar VLBI: Measurement precision by GHz BW observation. Atomic clocks and advanced technique: In + : 1 S 3 0 P 0 clock transition observed. Sr: Accuracy late 10 17, Abs. Freq. 9.3x Opt. time scale: Optical steering for 6 months within < 3ns. THz: Freq. Measurement system for 013TH 0.1 3THz has constructed. t 16