By employing a Doppler cancellation technique, optical frequency synthesis is achieved with stability and accuracy in the 10−20 range within 100 s. An offset between two optical frequency combs phase-locked at 1,542 nm is obtained as 5.4 × 10−21 at 1,063 nm within 105 s.
- Michele Giunta
- Wolfgang Hänsel
- Ronald Holzwarth
