Luminescence tuning and enhanced nonlinear optical properties of nanocomposites of ZnO–TiO 2

Abstract

In this article we present the spectral and nonlinear optical properties of ZnO–TiO 2 nanocomposites prepared by colloidal chemical synthesis. Emission peaks of ZnO–TiO 2 nanocomposites change from 340 nm to 385 nm almost in proportion to changes in E g . The nanocomposites show self-defocusing nonlinearity and good nonlinear absorption behaviour. The nonlinear refractive index and the nonlinear absorption increase with increasing TiO 2 volume fraction at 532 nm and can be attributed to the enhancement of exciton oscillator strength. ZnO–TiO 2 is a potential nanocomposite material for the tunable light emission and for the development of nonlinear optical devices with a relatively small limiting threshold.