Practical optical frequency measurement system around 1.5 μm based on an acetylene-stabilized laser-locked optical frequency comb

Abstract

We have developed a practical and precise frequency measurement system at 1.5μm telecommunication band. An electro-optic-modulator based optical frequency comb is phase-locked to a dither-free acetylene-stabilized laser to realize an optical frequency comb with frequency uncertainty of 10kHz (5×10−11) and the linewidth of 15kHz. The present frequency comb can be also used as an optical frequency reference grid defined by ITU-T (International Telecommunication Union, Telecommunication Standardization Sector). Using the present frequency measurement system, we have demonstrated the first optical frequency measurement of 12C16O overtone absorption lines around 1.56μm with the uncertainty of lower than 900kHz.