Elementary excitations in anisotropic narrow-band magnetic semiconductors

Journal Article · Sat Nov 01 04:00:00 EST 1986 · Theor. Math. Phys.; (United States)

DOI:https://doi.org/10.1007/BF01118154· OSTI ID:6834168

Erukhimov, M S; Ovchinnikov, S G

The Hamiltonian of a narrow-band s-d magnet with easy axis anisotropy is represented exactly in the form of the Hamiltonian of the degenerate Hubbard model. The diagram technique for Hubbard operators is used to find the spectrum of single-particle Fermi and Bose excitations at low temperatures and low carrier concentrations. The dependence of the spin-polaron band narrowing on the anisotropy is obtained. Two branches of magnon excitations are found; one determines the temperature corrections to the magnetization at small anisotropy, the other corrections at large anisotropy. It is shown that at T = O and for sufficiently great anisotropy spin waves are subject to collisionless Landau damping, and their group velocity has a logarithmic singularity at the boundary of the damping region.

• Research Organization: L.V. Kirenski Institute of Physics, Sibeman SSR Acad. of Sci.
• OSTI ID: 6834168
• Journal Information: Theor. Math. Phys.; (United States), Journal Name: Theor. Math. Phys.; (United States) Vol. 67:2; ISSN TMPHA
• Country of Publication: United States
• Language: English

Related Subjects

657002* -- Theoretical & Mathematical Physics-- Classical & Quantum Mechanics
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANGULAR MOMENTUM
BAND THEORY
BOSE-EINSTEIN GAS
CRYSTAL MODELS
DAMPING
ELECTRON DENSITY
ENERGY-LEVEL TRANSITIONS
EXCITATION
FERROMAGNETISM
HAMILTONIANS
LANDAU DAMPING
MAGNETIC SEMICONDUCTORS
MAGNETISM
MAGNONS
MATERIALS
MATHEMATICAL MODELS
MATHEMATICAL OPERATORS
MECHANICS
PARTICLE PROPERTIES
PERTURBATION THEORY
POLARONS
QUANTUM MECHANICS
QUANTUM OPERATORS
QUASI PARTICLES
SEMICONDUCTOR MATERIALS
SPIN
SPIN WAVES
THERMODYNAMICS