Performance scaling of a 10-GHz solid-state laser enabling self-referenced CEO frequency detection without amplification

• Published in: Optics express 2020-04, Vol.28 (9), p.12755-12770
• Main Authors: Krüger, Léonard M, Mayer, Aline S, Okawachi, Yoshitomo, Ji, Xingchen, Klenner, Alexander, Johnson, Adrea R, Langrock, Carsten, Fejer, Martin M, Lipson, Michal, Gaeta, Alexander L, Wittwer, Valentin J, Südmeyer, Thomas, Phillips, Christopher R, Keller, Ursula
• Format: Article
• Language: English
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/OE.391252

A simple and compact straight-cavity laser oscillator incorporating a cascaded quadratic nonlinear crystal and a semiconductor saturable absorber mirror (SESAM) can deliver stable femtosecond modelocking at high pulse repetition rates >10 GHz. In this paper, we experimentally investigate the influence of intracavity dispersion, pump brightness, and cavity design on modelocking with high repetition rates, and use the resulting insights to demonstrate a 10.4-GHz straight-cavity SESAM-modelocked Yb:CALGO laser delivering 108-fs pulses with 812 mW of average output power. This result represents a record-level performance for diode-pumped femtosecond oscillators with repetition rates above 10 GHz. Using the oscillator output without any optical amplification, we demonstrate coherent octave-spanning supercontinuum generation (SCG) in a silicon nitride waveguide. Subsequent f-to-2f interferometry with a periodically poled lithium niobate waveguide enables the detection of a strong carrier-envelope offset (CEO) beat note with a 33-dB signal-to-noise ratio.