What's New ?


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


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.

"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.

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(Related Site of Press Release[Japanese])
Link(Katori Project)


The web site of KATORI Project (Space-time information platform with a cloud of optical lattice clocks) was started. 【Link】

See the past information

Main Research

(1)Development of highly accurate/-precise frequency standard using optical lattice clocks.

see more detail

(2)Coherent atom control by atom-chip and/or atom IC

(3)Generation of Quantum entanglement by cooled atom

On research (1), we aim to achieve clock precision at 18-digit, and examine the constancy and time-fluctuation of physical constants based on our original idea of "Optical Lattice Clock". Research (2) and (3) aim to substitute conventional electronics with quantum electronics for creating new information processing systems, and we are carrying out research to realize quantum computer.

Right image: Strontium atom cluster cooled and captured by magneto-optical trap.
Fluorescence from ten-million atoms cooled down to mili-Kelvin temperature can be seen at the centerof the image.


To students who wish to attend the graduate school
We are recruiting motivated students who are going to join the master's course
If you wish to pay a visit to our lab.. Please contact