Enhanced nonlinear optical properties of LiNbO3 crystal embedded with CuZn alloy nanoparticles by ion implantation

LiNbO3 crystal, as a typical nonlinear optical material, has attracted considerable interest in photonic device applications. However, LiNbO3 shows weak nonlinear optical responses due to its low laser damage threshold. Herein, the optical nonlinearities of LiNbO3 are enhanced by inducing CuZn alloy nanoparticles (NPs). The structural and optical properties of LiNbO3 with embedded NPs were investigated in detail. The third-order nonlinear susceptibilities of CuZn: LiNbO3 nanocomposites exhibit nearly 4 orders of magnitude greater than the untreated LiNbO3 due to the localized surface plasmon resonance effect. Furthermore, the nanocomposites suffer conversion from reverse-saturable absorption to saturable absorption compared with the pure LiNbO3. This feature makes the nanocomposites a potential saturable absorber leading to the realization of efficient pulse lasers. (C) 2018 Elsevier B.V. All rights reserved.