Enhanced optical nonlinearity in β-AgVO3 nanobelts on decoration with Ag nanoparticles

Abstract

This paper reports on the optical nonlinearity of β-AgVO3 nanobelts and the modification in the physical mechanisms of nonlinear response on decorating with silver nanoparticles. The nanobelts are synthesized by a hydrothermal technique and characterized using SEM, TEM, and XRD etc. The nanobelts are found to exhibit large nonlinear optical absorption as revealed by open Z-scan measurements using 5 ns laser pulses at 532 nm. Nonlinearity appears to be arising from a combination of mechanisms of two photon absorption and saturable absorption (SA). Decoration with Ag nanoparticles is found to enhance the saturable absorption and alter the coefficient of nonlinear absorption of the nanobelts. Efficient optical limiting is demonstrated in both the nanobelt systems. We thank the Department of Science and Technology Unit on Nanoscience, IIT Madras for HRTEM. We also thank SAIF, IIT Madras for FESEM, and Defence Research Development Organization (DRDO), Govt. of India, for funding. The authors acknowledge the suggestions made by the reviewer which have helped to improve the quality of the paper considerably.