Ferrimagnetic Relaxation Measurements and Microwave Circuit Properties of Ferrite Ellipsoids

Abstract

The paper describes the results of an experimental investigation of relaxation processes in microwave ferrites. A new experimental procedure was developed in which the contribution of the uniform precessional mode to the relaxation may be separated from that of the other spin modes by controlling the interaction between the ferrite sample and its microwave environment. To characterize this interaction in detail, scattering matrix and lumped-element equivalent circuit representations were developed for a section of uniform waveguide containing a small ferrite ellipsoid. The circuit representation was then used to discuss radiation damping in a variety of microwave structures. In contrast to previous theories, the results are valid even when the interaction is large, provided that the sample is not too close to a waveguide wall. This 'wall effect,' which takes the form of a shift, broadening and distortion of the resonance line, is discussed in some detail. Transient solutions were obtained for the rate equations which describe the deviation of the z-component of magnetization from its equilibrium value, in the presence of appreciable radiation damping.

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Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1962
Accession Number
AD0612628

Entities

People

  • L. K. Anderson

Organizations

  • Stanford University

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Cavity Resonators
  • Circuits
  • Crystal Lattices
  • Crystal Structure
  • Crystals
  • Electromagnetic Radiation
  • Equations
  • Equivalent Circuits
  • Impedance
  • Materials
  • Measurement
  • Power
  • Resonance
  • Resonant Circuits
  • Resonant Frequency
  • Scattering
  • Transmission Lines

Fields of Study

  • Physics

Readers

  • Microwave Engineering.
  • Plasma Physics / Magnetohydrodynamics