Accession Number : AD0487286

Title :   THE GROWTH OF SINGLE CRYSTALS OF DOPED AND UNDOPED YTTRIA AND YTTRIUM ALUMINATE IN A HOLLOW CATHODE ZONE REFINER.

Descriptive Note : Quarterly progress rept. no. 2.

Corporate Author : MATERIALS RESEARCH CORP ORANGEBURG NY

Report Date : 15 JUL 1966

Pagination or Media Count : 15

Abstract : This report describes the results of Y2O3 and YAlO3 crystal growth efforts. A hollow cathode float-zone process was employed to achieve single crystal growth. During this period, single crystals of Y2O3 were grown but exhibited thermal cracking. Float-zone studies of 1 Y2O3 : 1 Al2O3 revealed that YAlO3 can be crystallized from the stoichiometric melt. It appears that YAlO3 crystallizes incongruently but that the molten zone compositional changes which occur during scanning may permit the growth of single crystal YAlO3. The instrumental changes made during this quarter include a new scanning system to permit improved rotation of crystal and feed rod during growth, and a dark space shielded hollow cathode gun. Several afterheater arrangements have been incorporated into the system to limit the thermal gradients on the growing crystal.

Descriptors :   *YTTRIUM COMPOUNDS), (*CRYSTAL GROWTH, (*LASERS, YTTRIUM COMPOUNDS), OXIDES, ALUMINATES, SINGLE CRYSTALS, ZONE MELTING, THERMAL STRESSES.

Subject Categories : Lasers and Masers

Distribution Statement : APPROVED FOR PUBLIC RELEASE