The growth of Nd: YAG single crystals

Abstract

Y3Al5O12 doped with 0.8% wt. Nd (Nd:YAG) single crystals were grown by the Czochralski technique under an argon atmosphere. The conditions for growing the Nd:YAG single crystals were calculated by using a combination of Reynolds and Grashof numbers. The critical crystal diameter and the critical rate of rotation were calculated from the hydrodynamics of the melt. The crystal diameter Dc = 1.5 cm remained constant during the crystal growth, while the critical rate of rotation changed from ωc = 38 rpm after necking to ωc = 13 rpm at the end of the crystal. The value of the rate of crystal growth was experimentally found to be 0.8-1.0 mm/h. According to our previous experiments, it was confirmed that 20 min exposure to conc. H3PO4 at 603 K was suitable for chemical polishing. Also, one-hour exposure to conc. H3PO4 at 493 K was found to be suitable for etching. The lattice parameter a = 1.201 (1) nm was determined by X-ray powder diffraction. The obtained results are discussed and compared with published data.