Pulsed laser ablation technique prepared gold nanoparticle in zinc tetraphenyl porphyrin for enhanced nonlinear optical response

Abstract

Zinctetraphenyporphyrine and Au nanoparticle-based nanocomposites (Au-ZnTPP) are examined for their nonlinear optical (NLO) behaviour and optical limiting property using z-scan experiment aiding pulsed laser that delivers 7ns pulses at 532 nm wavelength. The pulsed laser ablation on Au target in ZnTPP is the method of synthesis used for the nanocomposite preparation. ZnTPP with Au nanocomposite formation is confirmed from the quenching of the fluorescent emission spectrum and the modification of absorption spectrum. The introduction of the metal nanoparticle opens up additional energy transfer pathways, that can lead to enhanced excited-state absorption. Moreover, the augmentation is aided by local field effects of the Au NPs, contributes to increased interaction field strength on the surface of the NPs and the surrounding environment of the nanoparticle. The excited state absorption is revealed to be the major mechanism behind the observed nonlinear absorption and optical limiting activity. It is revealed that the suggested method could lead to the implementation of optical limiting-based devices suitable for photonic applications.