Second-harmonic performance of a-axis-oriented ZnO nanolayers on sapphire substrates -: art. no. 171108

We report on the nonlinear optical performance of sub-mu m ZnO films grown by metal organic aerosol deposition on r-plane sapphire substrates. These films display scale-like nanocrystalline structures. Layers of different crystallite sizes and shapes are studied. Both, x-ray diffractometry and the characteristic angular and polarization dependence of the second harmonic generation, indicate a strongly uniform a-axis orientation of the crystallites. Using 35-fs Ti:sapphire laser pulses, we demonstrate much higher conversion efficiencies for ZnO layers than previously reported. The robust performance at normal incidence makes this device suitable for advanced pulse characterization techniques. (C) 2005 American Institute of Physics.