Octave-spanning optical frequency comb based on a laser-diode pumped Kerr-lens mode-locked Yb:KYW laser for optical frequency measurement
Mitaki, M.; Sugiyama, K.; Kitano, M.
Applied Optics 57(18): 5150-5160
ISSN/ISBN: 1539-4522 PMID: 30117977 DOI: 10.1364/ao.57.005150
We developed an optical frequency comb based on a Yb:KYW laser. Soft-aperture Kerr-lens mode-locking at the cavity transverse-mode degeneration enabled us to generate 360 mW from a 750 mW pump laser diode. This resulted in spectral broadening over one octave using just a photonic crystal fiber. We achieved a free-running linewidth of 15 kHz in the carrier-envelope offset frequency by optimizing the cavity group delay dispersion, crystal position, and pump laser power, which led to a residual phase noise of 0.51 rad during phase-locking. We measured the frequency drift of a cavity-stabilized laser for a clock transition in Yb171+.