Q-switched vortex waveguide laser generation based on LNOI thin films with implanted Ag nanoparticles

Lithium-niobate-on-insulator (LNOI) thin films have gained significant attention in integrated photonics due to their exceptional crystal properties and wide range of applications. In this paper, we propose a novel approach to realize a Q-switched vortex waveguide laser by incorporating integrated lithium niobate thin films with embedded silver nanoparticles (Ag:LNOI) as a saturable absorber. The saturable absorption characteristics of Ag:LNOI are investigated using a home-made Z-scan system. Additionally, we integrate Ag:LNOI as a saturable absorber into a Nd:YAG ear-like cladding waveguide platform, which is prepared via femtosecond laser direct writing. By combining this setup with helical phase plates for phase modulation in the resonator, we successfully achieve a passive Q-switched vortex laser with a high repetition rate and narrow pulse duration in the near-infrared region. This work demonstrates the potential applications of LNOI thin films towards on-chip integration of vortex waveguide laser sources. (c) 2023 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

In this paper, a novel approach to achieve a Q-switched vortex waveguide laser by incorporating integrated lithium niobate thin films with embedded silver nanoparticles is proposed. The saturable absorption characteristics of the embedded silver nanoparticles are investigated, and the Niobate-on-insulator thin films are integrated into a Nd:YAG ear-like cladding waveguide platform. The successful realization of a high repetition rate and narrow pulse duration passive Q-switched vortex laser demonstrates the potential applications of lithium niobate thin films in on-chip integration of vortex waveguide laser sources.