Development of femtosecond optical frequency combs for optical frequency standards in NICT

Abstract

Optical frequency standards are being developed worldwide to lead a new definition of the unit of time. We are developing broadband optical frequency combs, which aims to count the laser frequency highly stabilized to the resonance of atomic reference and generate a rf frequency standard directly converted from the optical frequency. The developed frequency combs was successfully operated with a measurement accuracy of 3×10 -14 at the averaging time of 1 s. From the primary demonstration, it was confirmed to be available for the frequency stability measurement of a clock laser used in an optical frequency standards. The frequency combs will be key components for the development of optical atomic clock.