RESEARCH ON SPONTANEOUS MAGNETIZATION IN SOLID BODIES

Technical Report · Thu Feb 01 00:00:00 EST 1962

OSTI ID:4801506

Jacobs, I S; Rodbell, D S; Roth, W L

A number of research projects dealing with fundamental interactions and the microstructure of internal fields in selected magnetic materials were carried out. The nuclear magnetic resonance of Co/sup 59/ in metallic cobalt powders was examined. In addition to the absorption characteristic of Co/sup 59/ in face- centered cubic cobalt, there was found an additional group of absorptions, one of which is clearly associated with hexagonal close packed cobalt. The phenomenon of spin-flopping in antiferromagnetic MnF/sub 2/, in which the axis of antiferromagnetism is decoupled from the crystal axes, was observed by magnetization measurements in high pulsed magnetic fields. Its position coincided with the value, 93 kOe, predicted from measurements of antiferromagnetic resonance with millimeter microwaves. The temperature dependence of the magnetocrystalline anisotropy of facecentered cubic cobalt metal was examined by ferromagnetic resonance on single crystal thin films and submicron precipitate particles in Cu, at temperatures below the range in which this is the stable structure. Satisfactory agreement is obtained for a tenth power law between anisotropy and magnetization. A very brief review on pulsed field magnetization measurements in compounds was prepared. An investigation of magnetic exchange and structure in lanthanum manganite perovskite compounds spanning the transition between antiferromagnetism and ferromagnetism was performed using neutron diffraction and high field magnetization techniques. Evidence favored the single-phase canted spin model for this region over the model of a mixture of two crystallographically similar but magnetically distinct phases. Seven additional exploratory projects were undertaken, some of which hold considerable promise for development. (auth)

• Research Organization: General Electric Co. Research Lab., Schenectady, N.Y.
• DOE Contract Number: AF33(616)-7396
• NSA Number: NSA-16-025882
• OSTI ID: 4801506
• Report Number(s): ASD-TR-61-630
• Resource Relation: Other Information: Orig. Receipt Date: 31-DEC-62
• Country of Publication: United States
• Language: English

Related Subjects

PHYSICS
ABSORPTION
ANTIFERROMAGNETIC MATERIALS
ANTIFERROMAGNETISM
COBALT
COBALT 59
COMPOUNDS
CONFIGURATION
COPPER
CRYSTALS
DIFFRACTION
FERROMAGNETIC MATERIALS
FERROMAGNETISM
FREQUENCY
INTERACTIONS
LANTHANUM OXIDES
LATTICES
MAGNETIC FIELDS
MAGNETIC MATERIALS
MAGNETIC RESONANCE
MAGNETISM
MANGANESE COMPOUNDS
MANGANESE FLUORIDES
MEASURED VALUES
METALS
MICROWAVES
MONOCRYSTALS
NEUTRONS
NUCLEAR THEORY
POWDERS
PULSES
SOLIDS
SPIN
TEMPERATURE