Compact Q-Switched Vortex Waveguide Laser Modulated by Buried Ag Nanoparticles in Sio2

Abstract

Vortex beam, particularly pulsed vortex lasers, has expanded the potential applications in optics due to their unique wave-front phase structure and the determined photon orbital angular momentum. In this study, we present a novel approach including the integration of fused silica embedded with silver nanoparticles (Ag:SiO2) into the Nd:YAG waveguide platform for achieving nanosecond vortex pulses. Using a spiral phase plate for in-cavity phase modulation, we successfully demonstrate a Q-switched vortex laser with a high repetition rate in the megahertz range and short pulse width in the nanosecond regime. Additionally, we conduct a comprehensive analysis of the near-field distributions of Ag nanoparticles with varying sizes and distributions using COMSOL simulation. This study exemplifies the integration of silica-based photonic elements for realizing a high-stability and cost-effective nanosecond vortex laser system.

Keywords: Plasmonic nanoparticles, Localized surface plasmon resonance effect, Nonlinear optical response, Nd:YAG waveguide, Q-switched vortex laser