Abstract

Microresonator-based optical frequency comb generation based on four-wave mixing in ultra-high-Q microresonators has attracted significant interest during the past years [1-4]. However, a missing element to make these combs stand-alone tools for metrology applications is the independent stabilization of their carrier envelope offset frequency (e.g. by using an f-2f self-referencing technique). This has not been achieved to date. So far, stabilization of the offset frequency in microresonators required an additional reference frequency comb, which jeopardizes the advantage of having an integrated and small comb generator. Octave spanning microcombs on the other hand have only been demonstrated in microresonators with mode spacings beyond 200 GHz and under partial loss of coherence, which made it difficult to use them for optical self-referencing [5, 6].

© 2013 IEEE