Tailoring optical nonlinearities of LiNbO₃ crystals by plasmonic silver nanoparticles for broadband saturable absorbers

Abstract

We report on the synthesis of plasmonic Ag nanoparticles (NPs) embedded in a LiNbO₃ crystal (AgNP:LN) by ion implantation and its application as an efficient broadband saturable absorber (SA) to realize Q-switched pulsed laser generation at both visible and near-infrared wavelength bands. The nonlinear optical response of AgNP:LN is considered as a synergistic effect between Ag NPs and LiNbO₃. We apply the AgNP:LN as visible-near-infrared broadband saturable absorbers (SAs) into Pr:LuLiF₄ bulk and Nd:YVO₄ waveguide laser cavity, achieving efficient passively Q-switched laser at 639 nm and 1064 nm, respectively. This work paves a new way to tailor the nonlinear optical response of LiNbO₃ crystals by using plasmonic Ag NPs, manifesting the significant potential as broadband SAs in the aspect of pulsed lasing.