Gigahertz frequency combs from high-power diode-pumped solid-state lasers

Self-referenced optical frequency combs allow the characterization of optical frequencies with highest precision and provide the basis for optical metrology with applications such as optical clocks. An excellent laser technology for gigahertz frequency combs is diode-pumped solid-state lasers. This thesis describes the most recent research on the development of very compact, reliable and cost-effective gigahertz ultrafast lasers and the stabilization of novel high-power frequency combs.
The diode-pumped gigahertz solid-state lasers, presented in this thesis, represent the state-of-the-art with more than 20 kW of peak power and pulse durations of sub-60 fs. This new generation of stable high-power femtosecond gigahertz lasers was enabled by combining multiple key elements: robust SESAM modelocking, the novel gain material Yb:CaGdAlOindex4, reliable high-power diode-pumping and an all-optical Q-switching limiter.
The high potential of diode-pumped solid-state lasers for high-power frequency combs was demonstrated by two groundbreaking experiments: the first carrier-envelope-offset (CEO)-stabilization of a SESAM-modelocked thin disk laser and the first CEO-stabilization of a diode-pumped gigahertz laser. These research results mark milestones for frequency combs with unprecedented power per comb line and pave the way for the next generation of compact and reliable laser frequency combs.