Vyshnevskiy S. Regularities of the formation and nature of structure defects in Ti:sapphire grown in carbon-containing medium

Object of research is process of crystallization Al2O3:Ti from the melt in carbon-containig medium. To specify laws of formation and the nature of structural defects at crystallization Ti:sapphire in carbon-containig medium and to develop methods of improvement of optical characteristics of a material are the purpose of research. Results, novelty: Ti:sapphire crystal lattice supersaturation by ions of aluminium and Shottky defects during crystallization in carbon-containig medium and their subsequent coagulation are the reason of formation in the crystal of the submicron inclusions containing aluminium and its suboxides. It is shown, that heat treatment of Ti:sapphire in the medium with neutral chemical potential transform submicron inclusions in submivoids and promotes their destruction on the mechanism of vacancy dissolution or due to issue and movement of dispositions if compressing pressure are enclosed to a crystal. Micron faceted inclusions in Ti:sapphire grown in carbon-containig medium are voids which surface is formed by planes of the equilibrium form of a crystal. It is established, that consecutive annealing of sapphire in mediums with neutral and regenerative chemical potential is accompanied of annihilation of Shottky defects that allows to receive a crystal with the minimal optical absorption UV-region of the spectrum without the centers of painting on a basis anionic and cationic vacancies. Temperature dependence of factor of anionic vacancies diffusion in sapphire is determined.