Investigation on the bulk growth of $\alpha$-LiIO$_3$ single crystals and the influence of pH on its structural, morphological and optical characteristics

Bulletin of Materials Science

关键词: Optical materials;    crystal growth;    platform technique;    X-ray diffraction;    surface analysis;    frequency doubling.;   

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

$\alpha$-LiIO$_3$ is an excellent optical material exhibiting strong nonlinear optical, piezoelectric and elasto-opticproperties. However, its practical applications are limited by the insufficient reproducibility of the mentioned propertiescaused by the strong influence of the growth conditions, and, in particular, pH of the solution from which $\alpha$-LiIO$_3$3crystal is grown. Herein, we investigate to grow bulk size good quality crystals of $\alpha$-LiIO$_3$ based on the observed problems during its crystallization process. A systematic investigation was carried out to find the effect of pH on solubility, crystal growth, structural, surface and laser damage properties of $\alpha$-LiIO$_3$ single crystals. The structure and phase of LiIO$_3$ were confirmedby powder X-ray diffractometer analysis. The functional groups of the compound were identified using Fourier transforminfrared spectroscopy. Surface defects of the grown crystals were studied by etch patterns. The crystal grown at pH 10showed 10% optical transmission enhancement in comparison to the crystals grown at pH 2. The indirect optical bandgap ofthe crystal was reinvestigated using ultraviolet–Visible–near-infrared transmittance spectrum. The laser damage thresholdstudies of the crystals grown at pH 10 reveal the higher optical radiation stability against 532 nm laser. The second-ordernonlinear optical behaviour of $\alpha$-LiIO$_3$ crystals grown at different pH conditions have been investigated by using Kurtz andPerry powder technique with Nd:YAG laser pulses at the wavelength of 1064 nm.

【 授权许可】

CC BY