Overtone Raman scattering in lithium tantalate single crystals

Overtone bands in the spectral range of 1300–1920 cm$^{-1}$ have been found in Raman scattering spectrum of lithium tantalate single crystals. The Raman spectra were recorded in the 180$^{\circ}$ scattering geometry. The intensity of overtone transitions differs for different samples and, in some cases, is comparable with the Raman scattering intensity at the fundamental modes of a lithium tantalate single crystal.