Magnetooptic coupling coefficients for one- and two-magnon Raman scattering in the rutile-structure antiferromagnets FeF₂, MnF₂, CoF₂ and NiF₂

• Published in: Физика низких температур
• Date: 2012
• Main Authors: Lockwood, D.J., Cottam, M.G.
• Format: Article
• Language: English
• Published: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2012
• Subjects: Оптика и магнитооптика
• Online Access: https://nasplib.isofts.kiev.ua/handle/123456789/117242
• Journal Title: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Cite this: Magnetooptic coupling coefficients for one- and two-magnon Raman scattering in the rutile-structure antiferromagnets FeF₂, MnF₂, CoF₂ and NiF₂ / D.J. Lockwood, M.G. Cottam // Физика низких температур. — 2012. — Т. 38, № 7. — С.703-714. — Бібліогр.: 20 назв. — англ.

Inelastic light scattering intensities of magnetic excitations are governed by the magnetooptic coupling coefficients,
 which have been evaluated, for example, for the ferrimagnet Y₃Fe₅O₁₂ (YIG) and the metamagnets
 FeC₁₂ and FeBr₂. However, by far the most detailed studies to date have been performed on the classic rutilestructure
 antiferromagnets, and we summarize here the results obtained from the many experimental and theoretical
 investigations in these compounds for both one-magnon and two-magnon excitations. A comparison of the
 magnitudes of the various coupling coefficients for MnF₂, FeF₂, CoF₂, and NiF₂ reveals a surprising similarity
 in many coefficients. In one-magnon Raman scattering, the in-phase linear magnetooptic coefficient dominates
 and the main differences between MnF₂, FeF₂, and NiF₂ lie in the relative significance of the in-phase quadratic
 magnetooptic coefficient. Thus the quadratic coefficients are now seen to be of particular importance in determining
 the strength of the one-magnon scattering in a variety of magnetic insulators. In two-magnon Raman
 scattering, one magnetooptic coefficient dominates for all of these antiferromagnets. However, each of the other
 six coefficients are remarkably similar in magnitude, in general, and not negligible in most cases, indicating
 some universality in the way light interacts with the pairs of magnons of opposite and equal wave vector in rutile
 structure antiferromagnets.