Accession Number : AD0265205

Title :   PREPARATION OF SINGLE CRYSTALS OF YTTRIUM GALLIUM GARNET AND YTTRIUM ALUMINIUM GARNET AND INVESTIGATION OF PARAMAGNETIC RESONANCE SPECTRA OF FOUR RARE EARTH IONS IN THESE GARNETS

Corporate Author : OXFORD UNIV (ENGLAND) CLARENDON LAB

Personal Author(s) : BALL,M. ; GARTON,G.

Report Date : MAY 1961

Pagination or Media Count : 1

Abstract : An extensive survey is being conduc Methods of preparing suitable samples are described, and results of low temperature microwave resonance experiments with Yb(3+), Dy(3+), Er(3+), and Nd(3+) ions are given. For each of these ions, the ground state is a doublet which can be characterized by three principal values of a g tensor, and with one exception, all the principal values have been determined for these ions in both yttrium aluminium and yttrium gallium garnet. The local environment of the rareearth ions is far from being spherically or cubically symmetrical, so that the individual rare earth ions have magnetic properties which are very anisotropic. The relation of these results to the observed anisotropies in rare earth iron garnets and rare earth doped YIG are discussed. AD-265 20 Div. 25, 17 (TIPSM/BRW) OTS price $4.60 Ordnance Materials Research Office, Watertown, Mass. HIGH LOADING RATES IN ETALS, by R. Beeuwkes, Jr. June 59, 42p. incl. illus. (MRL rep. o. Proj. TB 4-001 and DA 5-93-32-001) Unclassified repot DESCRIPTORS: (*Mechanics, *Metals, Alloys, Ordnance steel, Gun barrels, Load distribution, Velocity, Plasticity, Deformation,tresses, Mechanical properties, Tensile properties, Fracture (Mechanis, g (Mechanics), Impact shock, Hardness, Terminal ballisic,test methods, Tests, Analysis.) Photoelastic materials. High loading rate effects are found to commonly occur in both low and high speed apparatus nd tess. Though commonly disregarded, it is important to understand these effects as shown by examples which also indicate how low speed tests may oftn b satisfactorily substituted for high speed tests. The severity of rates, judged by materials behavior which is considered the outstanding criterion, is found to be crucially dependent on temperature. (Author)

Descriptors :   *GARNET, *RARE EARTH COMPOUNDS, ALUMINUM COMPOUNDS, CRYSTAL STRUCTURE, CRYSTALS, DYSPROSIUM, ERBIUM, GALLIUM COMPOUNDS, GROWTH(PHYSIOLOGY), IONS, MAGNETIC PROPERTIES, MATHEMATICAL ANALYSIS, NEODYMIUM, NUCLEAR SPINS, PARAMAGNETIC RESONANCE, SILICATES, SINGLE CRYSTALS, THEORY, YTTRIUM COMPOUNDS

Distribution Statement : APPROVED FOR PUBLIC RELEASE