Anisotropy of Attenuation of Acoustic Waves in Pure and Doped LiNbO3 Crystals

The effect of magnesium and zinc impurities on the magnitude and anisotropy of the velocity and attenuation coefficient of high-frequency acoustic waves in lithium niobate crystals has been studied. It is shown that these impurities greatly reduce the attenuation of longitudinal waves and practically have little effect on the attenuation of transverse waves. The attenuation anisotropy in pure and doped lithium niobate crystals was determined on the basis of the Akhiezer mechanism using imaginary elastic constants.