961 research outputs found
H-T Phase Diagram of Rare-Earth -- Transition Metal Alloy in the Vicinity of the Compensation Point
Anomalous hysteresis loops of ferrimagnetic amorphous alloys in high magnetic
field and in the vicinity of the compensation temperature have so far been
explained by sample inhomogeneities. We obtain H-T magnetic phase diagram for
ferrimagnetic GdFeCo alloy using a two-sublattice model in the paramagnetic
rare-earth ion approximation and taking into account rare-earth (Gd) magnetic
anisotropy. It is shown that if the magnetic anisotropy of the -sublattice
is larger than that of the -sublattice, the tricritical point can be at
higher temperature than the compensation point. The obtained phase diagram
explains the observed anomalous hysteresis loops as a result of high-field
magnetic phase transition, the order of which changes with temperature. It also
implies that in the vicinity of the magnetic compensation point the shape of
magnetic hysteresis loop is strongly temperature dependent.Comment: 8 pages, 3 figure
Extraordinary magnetooptical effects and transmission through the metal-dielectric plasmonic systems
We report on significant enhancement of the magnetooptical effects in
gyrotropic systems of a metallic film perforated by subwavelength hole arrays
and a uniform dielectric film magnetized perpendicular to its plane.
Calculations, based on a rigorous coupled-wave analysis, demonstrate the
Faraday and Kerr effect spectra having several resonance peaks in the near
infrared range, some of them coinciding with transmittance peaks. Qualitative
analysis revealed that magnetic polaritons being coupled magnetic-film
waveguiding modes with surface plasmons play a crucial role in the observed
effect.Comment: 10 pages, 3 figure
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