The Past Information

2021

2021.05.31

A paper on a transportable strontium optical lattice clocks has been published. Link: Selected papers

2020

2020.5.15

Three 4th grade students (Mr. Ishizaki, Mr. Nishida, and Mr. Fujiwara) have been assigned to Katori Lab.

2020.5.4

A new paper of "Direct measurement of the frequency ratio for Hg and Yb optical lattice clocks and closure of the Hg/Yb/Sr loop" by Omae-san and Katori-sensei et al. was published in Optics Express. 【Link】

2020.4.7 Press Release

Press release was jointly conducted by the University of Tokyo, RIKEN, GSI, Shimadzu Corporation, Tobu Tower Skytree Corporation and JST.

Overview:
"The world's first successful development of a portable optical lattice clock with 18-digit accuracy"
Verification of general relativity at Tokyo Skytree
The world's first successful development of two portable optical lattice clocks with 18-digit accuracy. Using these two optical lattice clocks, we performed high-precision observations of gravitational redshift above and below the The Tokyo Skytree, and successfully verified general relativity on the ground.

Paper:
Masao Takamoto, Ichiro Ushijima, Noriaki Ohmae, Toshihiro Yahagi, Kensuke Kokado, Hisaaki Shinkai & Hidetoshi Katori, Test of General Relativity by a Pair of Transportable Optical Lattice Clocks, Nature Photonics (2020).
DOI Number: 10.1038/s41566-020-0619-8

Link（paper）
Link（Related Site of Press Release[Japanese]）
Link（JST-Mirai Space-time information platform with a cloud of optical lattice clocks project）

2020.3.25

The web site of JST-Mirai Program (large-scale Type) Space-time information platform with a cloud of optical lattice clocks project was started. 【Link】

2019

2019.11.20

PRESS: ” Superradiance from Lattice-Confined Atoms inside Hollow Core Fibre” published in Communications Physics, Oct.2019. 【Link】 【Link】 【Link】 【Link】

2019.9.17

PRESS: ” Narrow-line Cooling and Determination of the Magic Wavelength of Cd” published in Physical Review Letters, Sep.2019. 【Link】 【Link】 【Link】 【Link】

2019.8.1

Katori Laboratory moved to Faculty of Engineering Bilg. 9 in Yayoi campus. Please see the link. 【Link】

2019.3.28

Kick-off meeting; JST MIRAI Large Project, “Space-time information platform with a cloud of optical lattice clocks”, starting from Nov. 2018, was held at Koshiba Hall in March 28th, 2019.

2019.1.18

PRESS: ”Operational Magic Intensity for Sr Optical Lattice Clocks” published in Physical Review Letters, Dec.2018. 【Link】 【Link】 【Link】 【Link】 【Link】

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2018

2018.10.3

Two sets of optical lattice clock system were carried and installed to Tokyo Sky Tree for gravitational potential measurement from Oct. 2nd midnight to Oct 3rd morning. NHK Ohayo Nippon, Asahi Sinbun, The Mainichi reported on it.

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2017

2017.11.24

NHK News 7 reported on Prof. Katori and his group’s research planning of gravitational potential measurement with their optical lattice clock at Tokyo Sky Tree.

2017.11.21

Prof. Katori was awarded "The 14th Leo Esaki Prize" for "Invention and realization of high-precision optical lattice clocks".

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2016

2016.8.16

PRESS: “Geopotential measurements with synchronously linked optical lattice clocks” published in Nature Photonics

2016.4.25

Homepage has renewed

2016.4.18

International workshop report "View From…Challenges in Precision Science, A never-ending quest " was published in Nature Photonics, April 2016
doi:10.1038/nphoton.2016.48

2016.3.1

PRESS: "Accelerating comparisons of ytterbium and strontium optical lattice clocks: Swift, ultra-precise measurements of frequency ratios may open new windows for science"

"Frequency Ratio of Yb and Sr clocks with 5×10^-17 uncertainty at 150 seconds averaging time", Nat. Photon. (2016)
doi：10.1038/nphoton.2016.20

To Media reports

2016.2.1

Prof. Katoriwas awarded "JSAP Outstanding Achievement Award" for "Pioneering research on optical lattice clocks"

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2015

2015.8.14

Research achievement, “Just a second… A mercury-atom-based clock has an accuracy surpassing that of the standard definition of the second” was published in “RIKEN RESEARCH”.

2015.5.27

PRESS: “Highly-precise comparison of Hg and Sr optical lattice clocks”

“Frequency Ratio of ¹⁹⁹Hg and ⁸⁷Sr Optical Lattice Clocks beyond the SI Limit”, Phys. Phys. Rev. Lett. 114,230801 (2015)
doi：10.1103/PhysRevLett.114.230801
To Media reports

2015.4.15

Dr. Takamoto (Research Scientist, RIKEN) was awarded “The Commendation for Science and Technology by the Minister of Education, Culture, Sports, Science and Technology (MEXT), Prize for The Young Scientists’ Prize”.

2015.3.12

Prof. Katori was awarded “Japan Academy Prize” for ”Invention of the Optical Lattice Clock and its development“.

2015.2.10

PRESS: ”Development of highly-precise optical lattice clocks successfully ? a step towards future time standard”

“Cryogenic optical lattice clocks” Nat. Photon., Vol.9, 185-189 (2015)
doi:10.31038/NPHOTON.2015.5
To Media reports