Investigation of acoustic, optical and photorefractive properties of multicrystals of lithium niobate doped with zinc in the area of concentrations of 5,38-9,0 mol.% Zn

Abstract

Obtaining optical materials based on lithium niobate with controlled optical properties is an important task of modern materials science. To date the problem of obtaining heavily doped LiNbO3 crystals of optical quality with a macroscopically uniform impurity distribution has not been solved. In this work a comparative analysis of studies of the acoustic, optical and photorefractive properties of LiNbO3:Zn lithium niobate single crystals obtained by direct and homogeneous doping from melts with concentrations of 5,38-9,0 mol% Zn has been carried out. The following methods have been used: piezoacoustics, photoinduced light scattering and laser conoscopy. The values of the static piezoelectric modulus have been determined. According to these values, all crystals are single-domain. Studies of crystals have confirmed the absence of a photorefractive effect in them. It was established that LiNbO3:Zn crystals grown on the basis of the method of homogeneous doping with concentrations in the melt of 6,8-9,0 mol% Zn are characterized by the highest structural and optical uniformity. This is of interest for the technology of growing large zinc-doped lithium niobate crystals by the Czochralski method.

Keywords

• lithium niobate
• zinc doping
• single crystal
• static piezoelectric module
• photoinduced light scattering
• laser conoscopy
• optical uniformity