INVESTIGATION OF MAGNETIC RESONANCE IN STRONGLY COUPLED DIPOLE SYSTEMS.

Abstract

The initial permeability of some polycrystalline garnets was measured form 0 to 12 KMc. The samples were obtained by pulverizing single crystals. The resonances observed depend on the sample density. Only for the densest samples are two distinct peaks observed. The spin-wave spectra of thin permalloy films was observed for various boundary conditions. The results are correlated with a simple model in which the mode numbering and degree of pinning are considered. The validity of the ''square law'' is discussed. Modifications of known methods of crystal growing are described. They result in better quality large single crystals, that is, ones that possess fewer flux inclusions and cavities. Static and pulse measurements are described. Switching times of 1 nanosecond have been observed in YIG. Small spheres of garnets were polished by a new technique. This polishing has a profound influence on the line width. The anisotropy of the line width have been investigated. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1963
Accession Number
AD0421126

Entities

People

  • A. H. Morrish

Organizations

  • University of Minnesota

Tags

DTIC Thesaurus Topics

  • Anisotropy
  • Boundaries
  • Crystals
  • Inclusions
  • Magnetic Resonance
  • Measurement
  • Nanosecond Time
  • Permeability
  • Polishing
  • Polycrystals
  • Resonance
  • Single Crystals
  • Spectra
  • Spin Waves
  • Switching

Fields of Study

  • Physics

Readers

  • Microwave Engineering.
  • Superconducting Magnet Technology
  • Theoretical Analysis.