Accession Number:

AD0775211

Title:

Preparation and Single Crystal Growth of LiYF4 Laser Materials.

Descriptive Note:

Final rept. 1 Jan-31 Dec 73,

Corporate Author:

LITTON SYSTEMS INC MORRIS PLAINS N J LAMBDA-AIRTRON DIV

Report Date:

1974-02-01

Pagination or Media Count:

37.0

Abstract:

The report describes techniques for preparation of high purity fluorides suitable for laser crystal hosts. Growth methods for LiYF4 were also developed using a constant flow of HF. The YF3 and rare earth fluorides are prepared from 5 or 6-9s polycrystalline oxides. A special platinum reactor was designed to convert oxides to fluorides via an HF reaction. Trifluorides were prepared at 800-900C and melted under HF at 1050-1200C. This prevented formation of oxide and oxyfluoride impurities in the melt. Growth of LiYF4 was accomplished in a resistively heated platinum apparatus and crucible using a modified Czochralski method. Growth occurred under a fixed pressure of HF. Preliminary results gave crystals of high optical quality, free of OH-, scattering sites, and low impurity level. The procedures should be applicable to other YLF materials in volume production. Author

Subject Categories:

  • Lasers and Masers
  • Crystallography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE