The Single Crystal Growth and Laser Rod Fabrication of Neodymium Doped Yttrium Vanadate.
Abstract
Good quality (100) YVO4 with 1 atomic % Nd was grown from stoichiometric melts contained in RF heated 50 x 50mm iridium crucibles. Initial growth experiments used reacted phosphor grade YVO4 and Nd:VO4 until the growth parameters of structurally sound crystals were determined. Stoichiometric solid state reactions of the component high purity oxides, V2O5 (<15 ppm impurities), 99.999% Y2O3, and 99.99% Nd2O3 were then used. During growth a significant amount of V2O5 was vaporized which led to changes in melt composition and crystallization temperatures. the YVO4 melt slowly decomposed into YVO3 and O2. High partial pressures of O2 reduced decomposition rates, but the amount of crucible oxidation was very severe. After prolonged heating, V2O5 depletion and sample decomposition limited growth. Experiments indicated YVO4:Nd could be grown from a nonstoichiometric composition of 10 mole% excess Y2O3 at lower temperatures where V2O5 vaporization was noticeably less. The crystal-melt interface and thermal gradient were adjusted to produce the best growth in a 99.5% N2-O.5% O2 atmosphere at a pull rate of 2.54mm/hr and a rotation rate of 4 rpm. Boules of (100) YVO4:Nd up to 90mm long x 6mm x 20mm were grown with excellent diameter control. Preferred growth occurred along (001) with large smooth facets on (010) planes the entire boule length.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1978
- Accession Number
- ADA062707
Entities
People
- Larry E. Drafall
- Roger F. Belt