Optical constants and dispersion behavior of PbMg1/3Nb2/3O3 single crystals

The optical properties of PbMg1/3Nb2/3O3(PMN) single crystals in the wavelength range of 300–1700 nm have been investigated using Variable Angle Spectroscopic Ellipsometer (VASE). The refractive indices and extinction coefficients have been obtained. The optical band gap energy of PMN single crystal was derived to be about 3.41 eV. The Sellmeier optical coefficients E0, λ0, S0, and Ed were calculated by fitting the single-term oscillator equation. The transmission ratio of PMN single crystal ranging from 200 to 2200 nm has also been investigated using UV–visible–NIR spectrometer. The transmission ratio is above 60% in near IR region and the reflection loss is calculated to be about 20%.