Growth and optical properties of different compositions OfLiNbO₃ single crystal fibers

In this study the laser-heated pedestal growth (LHPG) method was used to grow lithium niobate (LiNbO₃) single crystal fibers with different compositions ratios [Li₂CO₃MNb₂O₅] = 44:56, 45:55, 46:54, 47:53, 48:52, 48.3:51.4, 49:51 and 50:50 achieved by different seed rods. X-ray Single-Crystal Diffractometer (X-Ray/CCD) was used to determine the lattice parameters and crystalline structure of the crystals. The UV absorption spectrum, Fourier-transform infrared spectrometer and Raman scattering spectroscopy results were used to find the optical properties and standard characterization of the different LiNbO₃ single crystals. We note that the wavelength of the UV absorption edge and the wave number of the O-H absorption peak were less when the Li₂O composition was large. The plotted results tended to fit a Gaussian curve. The Full-Width Half-Maximum (FWHM) of the Raman peak found at 152 cm of the E(TO) mode decreased linearly as the amount of the Li₂O composition increased. The Raman scattering results showed that the structure at the UNbO₃ crystal became more rigid when the amount of the Li₂O composition increased.