Extensive study on pulsed operation of nanocarbon-integrated waveguide lasers

Abstract

Efficient pulsed lasers in compact cavity designs provide considerable potential for integrated photonics and practical application areas of lasers including spectroscopy, metrology, microscopy, and microprocessing. This thesis addresses extensive study of pulsed operation of compact waveguide solid-stae lasers. The mode-locking of waveguide laser can achieve high repetition frequency of ultrafast pulses. The gigahertz-level high repeition rate is especially benefical for fast sampling, precise processing, and astro-combs. To demonstrate pulsed opeartion, nanocarbon-based saturable absorbers are widely applied in various types of laser cavities. Their unique optical properties including high 3rd-order nonlinearity, ultrabroadband absorption, ultrashort relaxation times, and flexible application tyeps make possible to be efficiently integrated into miniaturized laser system. Therefore, this thesis studies pulsed opeartion of nanocarbon-integrated compact waveguide lasers. Critical factors for pulsed operation including pumping efficiency, saturable abnsorber interaction types, transition mechanism up to continuous-wave mode-locking from Q-switching, waveguide gain medium, beam-splitter-type waveguide, and noise characteristies are discussed based on experimental and theoretical analysis of waveguide lasers. The extensive understanding of pulsed waveguide laser provides basis to achieve higher performance of compact ultrafast lasers.