Surface plasmon enhanced linear and nonlinear optical properties of lycopene bioconjugated silver nanoparticles

The synthesis of lycopene@silver nanoparticle bioconjugates by pulsed laser ablation in liquid was studied. The ablation product was characterised by UV-Vis optical absorption, Raman spectroscopy and transmission electron microscopy (TEM). The experimental results were confirmed by the computational studies. Furthermore, to assess the influence of the surface plasmon on nonlinear optical (NLO) responses, in this work, we investigated the NLO properties of lycopene@silver systems using the density functional theory (DFT) approach at the B3LYP/6-311G/LANL2DZ level. In addition to molecular descriptors, the static and dynamic (at the working wavelength of the device, 1064 nm and 532 nm) polarizability (𝛼), first hyperpolarizability (β), and second hyperpolarizability (𝛾) were calculated. Compared to the lycopene molecule, results of the lycopene@Ag ₁₈ system show increased values of +2.88 D, 115.86 x 10 ^-24 esu, 198.94 x 10 ^-30 esu, and 33.73 x 10 ^-34 esu, for 𝜇, 𝛼 ₀ , β ₀ , and 𝛾 ₀ , respectively. We found that lycopene@Ag systems have enhanced NLO properties, allowing us to hypothesise that the lycopene@AgNPs with the increased size of the AgNPs might be suitable as third-order NLO materials with increased stability, high flexibility in molecular engineering, and flexible photonic devices. Bioconjugated lycopene with AgNPs enhances local field effects, boosting both linear and NLO attributes.