Accession Number : AD0482418

Title :   LONGITUDINAL SUSCEPTIBILITY OF POROUS, POLYCRYSTALLINE YIG AT MICROWAVE FREQUENCIES.

Descriptive Note : Technical memo.,

Corporate Author : RAYTHEON CO WALTHAM MA RESEARCH DIV

Personal Author(s) : Kohane, T. ; Schloemann, E.

Report Date : 25 OCT 1965

Pagination or Media Count : 8

Abstract : A theory of the longitudinal susceptibility (response to an rf field applied parallel to the dc field) of magnetic materials with a nonuniform saturation magnetization is described. According to this theory, the imaginary part of the longitudinal susceptibility, considered as a function of dc magnetif field, should show an absorption peak whose height is proportional to the porosity, whereas the width is substantially independent of porosity and approximately given by 2 pi M, where M is the average saturation magnetization. The real part of the susceptibility is negative on the low field side, positive on the high field side, of the absorption peak. Measurements on porous, polycrystalline YIG at room temperature and X-band are reported. The data agree quite well with the theoretical predictions, provided that allowance is made for the damping of the spin waves that give rise to the longitudinal susceptibility. (Author)

Descriptors :   (*FERROMAGNETIC MATERIALS), (*FERROELECTRIC CRYSTALS, ELECTROMAGNETISM), ANISOTROPY, MICROWAVE FREQUENCY, ELECTROMAGNETIC FIELDS, MATHEMATICAL PREDICTION, POROSITY, DEFECTS(MATERIALS), ELECTRICAL PROPERTIES, YTTRIUM, FERRITES, GARNET, IRON ALLOYS, MAGNETOOPTICS, RADIOFREQUENCY, X BAND.

Subject Categories : Crystallography
      Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE