Low phase noise optical frequency comb

Phase noise is a fundamental characteristic of an optical frequency comb (OFC). Low phase noise OFCs are powerful tools for the comparison of different optical clocks,precision spectroscopy, and time and frequency transfer. After a description of the phase noise, we summarize the noise sources affecting OFCs and the techniques for suppressing the noise, and present several low phase noise OFC systems developed in our lab. Finally, we review the prospects for future developments.