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 ?c=38 rpm after necking to ?c=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.

Simulation of transport processes during Czochralski growth of YAG crystals

“…For the parameters selected, the pull velocity was in the range of 1-2 mm/h, the deformation of melt-crystal interface being in the range of 1-2 mm. Comparable values have been quoted for industrial pullers for the growth of YAG crystals [30].…”

“…The influence of an opaque melt and a fully transparent melt have been studied. The numbers quoted here are based on the literature of Czochralski growth of YAG crystals [30].…”

Distribution of Neodymium and properties of Nd:YAG crystal by horizontal directional solidification

“…Recently, Neodymium-doped yttrium aluminum garnet (Nd:YAG) is ordinarily produced as the most suitable and commercial laser material for various modes of operation (CW, pulsed, Q-switched, mode locked and cavity dumped) [1][2][3][4][5][6]. Therefore, there has been a continuing interest in the development of the technology of YAG garnet crystal growth.…”

“…Therefore, there has been a continuing interest in the development of the technology of YAG garnet crystal growth. The main Nd:YAG growth techniques are the conventional Czochralski (Cz) and temperature gradient technique (TGT) [1,2,4]. Because the radius of Nd 3 þ ion (1.12Å) is larger than the radius of Y 3 þ ion (1.01Å), the difference of about 10.9% makes it complicated to incorporate it into the Y 3 þ site of the crystal lattice.…”

Nd induced changes in IR spectra of CaWO4 single crystals

“…In our previous paper [12,13], we obtained CaWO 4 and Nd:CaWO 4 single crystals using the Czochralski technique taking hydrodynamics equations into account, as we have successfully done for many oxide single crystals (Bi 12 SiO 20 [17], Bi 12 GeO 20 [18], sapphire [19], Nd:YAG [20], etc.). The aim of the present paper was to reveal and explain the observed peculiarities and the Nd induced changes in the infrared spectra of the high quality CaWO 4 and Nd:CaWO 4 single crystals.…”