Potassium sodium niobate(KNN) powders were synthesized using a modified sol-gel method.The metal precursors us...
Yang Cao,Kongjun Zhu~*,Hongjuan Zheng,Jinhao Qiu,Honghui Gu State Key Laboratory of Mechanics and Control of Mechanical Structures,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,P.R.China
0.91Pb(Zn1/3Nb2/3)O3-0.09PbTiO 3(PZN-9%PT) single crystals with different orientations are investigated by using a spectroscopic ellipsometer,and the refractive indices and the extinction coefficients are obtained.The Sellmeier dispersion equations for the refractive indices are obtained by the least square fitting,which can be used to calculate the refractive indices in a low absorption wavelength range.Average Sellmeier oscillator parameters E o,λ o,S o,and E d are calculated by fitting with the single-term oscillator equation,which are related directly to the electronic energy band structure.The optical energy bandgaps are obtained from the absorption coefficient spectra.Our results show that the optical properties of [001] and [111] poled crystals are very similar,but quite different from those of the [011] poled crystal.
