Magnetic excitations in the itinerant antiferromagnets Mn/sub 3/Si and Fe-doped Mn/sub 3/Si

Journal Article · Sat Aug 01 00:00:00 EDT 1987 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.36.2181· OSTI ID:6161880

Tomiyoshi, S; Yamaguchi, Y; Ohashi, M; Cowley, E R; Shirane, G

Magnetic excitations in the itinerant antiferromagnets Mn/sub 3/Si and Fe-doped Mn/sub 3/Si have been measured at low temperatures by inelastic scattering of neutrons. Mn/sub 3/Si is an incommensurate antiferromagnetic with magnetic Bragg points of the form (h,k,l) +- (delta,delta,delta) with delta = 0.425. Fe-doped Mn/sub 3/Si is a commensurate antiferromagnet with delta = (1/2. Its low-energy magnetic excitations have a linear dispersion relation with a slope of approximately 30 meV A, but above 6 meV, the slope increases so that the ''cone'' of the dispersion relation becomes a ''chimney.'' Well-defined excitations have been observed at energies up to 7.5k/sub B/T/sub N/ (15 meV). In pure Mn/sub 3/Si, a similar dispersion cone exists around each satellite magnetic Bragg point with a slope of approximately 37 meV A. The two dispersion cones from a pair of satellite points intersect at about 5 meV. Above this energy the intensity of the inelastic peaks changes drastically, indicating a strong interaction between the cones. For both phases, the damping is very large and increases almost linearly with energy.

• Research Organization: Research Institute for Iron, Steel and Other Metals, Tohoku University, Sendai 980, Japan
• OSTI ID: 6161880
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Vol. 36:4
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
MANGANESE SILICIDES
MAGNETIC PROPERTIES
NEUTRON DIFFRACTION
SPIN WAVES
ANTIFERROMAGNETIC MATERIALS
COLLECTIVE EXCITATIONS
DAMPING
DISPERSION RELATIONS
DOPED MATERIALS
INELASTIC SCATTERING
IRON ADDITIONS
ALLOYS
COHERENT SCATTERING
DIFFRACTION
ENERGY-LEVEL TRANSITIONS
EXCITATION
IRON ALLOYS
MAGNETIC MATERIALS
MANGANESE COMPOUNDS
MATERIALS
PHYSICAL PROPERTIES
SCATTERING
SILICIDES
SILICON COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
360204* - Ceramics
Cermets
& Refractories- Physical Properties