Third order nonlinear optical properties of lithium zinc calcium fluoroborate glasses embedded with Au–Ag nanoparticles

Herein, fluoro borate glasses embedded with gold (Au) and silver (Ag) nanoparticles (NPs)were fabricated through melting and quenching process. The surface plasmon resonance (SPR) peak sat 450 nm, 480 nm, 510 nm, 560 nm, 590 nm, and 610 nm in the optical absorption spectra provides primary evidence respectively for the formation of AgNPs and Au NPs, respectively, in the glass hosts. The third–order nonlinear optical (NLO) properties of titled glasses embedded with Au and Ag NPs were ascertained in near–infrared spectral region using femtosecond laser pulses to understand the efficacy of Au and Ag NPs on the said properties. Glass with 0.17 mol% of Au and 0.34 mol % of Ag has shown a higher value of nonlinear refractive index of 7.15 × 10−19 cm2/W and nonlinear absorption coefficient of 2.12 × 10−11 m/W in the investigated system. This work highlights the geometrical dependence that is accountable for tailoring the NLO properties of Au and Ag bimetallic NPs.