Accession Number : AD0698123

Title :   THE EFFECT OF TWO-MAGNON SCATTERING ON PARALLEL-PUMP INSTABILITY THRESHOLDS.

Descriptive Note : Technical rept.,

Corporate Author : HARVARD UNIV CAMBRIDGE MASS DIV OF ENGINEERING AND APPLIED PHYSICS

Personal Author(s) : Sage,Jay Peter

Report Date : JUL 1969

Pagination or Media Count : 126

Abstract : Following a general description of the important properties and symmetries of the parallel-pump coupling and of two-magnon scattering, several theoretical approaches to the problem of the effect of two-magnon scattering on the parallel-pump instability threshold are explored. A successful approach, based on the rate of energy flow among the spinwave modes and involving only elementary mathematical tools, is developed. Extensive experimental data on the wave vector dependence of delta H sub k over a wide range of temperatures in ferromagnetic CdCr2Se4 are also presented. Results of theoretical calculations at several temperatures are compared with these data, and interesting information about spinwave renormalization and the dominant multimagnon scattering mechanisms at temperatures up to about 90% of the Curie temperature is obtained. (Author)

Descriptors :   (*FERROMAGNETIC MATERIALS, MAGNETIC RESONANCE), (*MAGNETIC MOMENTS, INTERACTIONS), CADMIUM COMPOUNDS, CHROMIUM COMPOUNDS, SELENIDES, SINGLE CRYSTALS, CRYOGENICS, THESES

Subject Categories : Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE