Fermionic representation for the ferromagnetic Kondo lattice model -- diagrammatic study of spin-charge coupling effects on magnon excitations

Abstract

A purely fermionic representation is introduced for the ferromagnetic Kondo lattice model which allows conventional diagrammatic tools to be employed to study correlation effects. Quantum 1/S corrections to magnon excitations are investigated using a systematic inverse-degeneracy expansion scheme which incorporates correlation effects in the form of self-energy and vertex corrections, while explicitly preserving the continuous spin-rotation symmetry. Magnon self-energy is studied in the full range of interaction strength, and shown to result in strong magnon damping and anomalous softening for zone boundary modes, which accounts for several zone-boundary anomalies observed in recent spin-wave measurements of ferromagnetic manganites.

16 pages, 9 figures

References in corpus (19)

• Colossal Magnetoresistant Materials: The Key Role of Phase Separation
• Double Exchange Alone Does Not Explain the Resistivity of $L{a}_{1-x}S{r}_{x}Mn{O}_3$
• Magnon Damping by magnon-phonon coupling in Manganese Perovskites
• Spin Excitation Spectrum of La${}_{1-x}{A}_x$MnO${}_3$
• Spin Wave Theory of Double Exchange Ferromagnets
• Evolution of spin-wave excitations in ferromagnetic metallic manganites
• A novel spin wave expansion, finite temperature corrections and order from disorder effects in the double exchange model
• Magnons in Ferromagnetic Metallic Manganites
• Spin waves throughout the Brillouin zone and magnetic exchange coupling in ferromagnetic metallic manganites La${}_{1-x}$Ca${}_x$MnO${}_3$ ($x=0.25,0.30$)
• Low Temperature Magnetic Properties of the Double Exchange Model
• Ferromagnetism in the t-t' Hubbard model: interplay of lattice, band dispersion, and interaction effects studied within a Goldstone-mode preserving scheme
• Effects of the On-Site Coulomb Repulsion in Double Exchange Magnets
• Three--body Correlation Effects on the Spin Dynamics of Double--Exchange Ferromagnets
• Non--Heisenberg Spin Dynamics of Double-Exchange Ferromagnets with Coulomb Repulsion
• Magnons in the ferromagnetic Kondo-lattice model
• Spin waves in a band ferromagnet: spin-rotationally symmetric study with self-energy and vertex corrections
• Spin dynamics in the diluted ferromagnetic Kondo lattice model
• Clustering induced suppression of ferromagnetism in diluted magnets
• Quantum and thermal fluctuations in a two-dimensional correlated band ferromagnet -- Goldstone-mode preserving investigation with self-energy and vertex corrections

Cited by in corpus (9)

• Metallic Ferromagnetism in the Kondo Lattice
• Spin-charge coupling in a band ferromagnet: magnon-energy reduction, anomalous softening, and damping
• Orbital fluctuations, spin-orbital coupling, and anomalous magnon softening in an orbitally degenerate ferromagnet
• Interacting spin waves in the ferromagnetic Kondo lattice model
• Spin-charge and spin-orbital coupling effects on spin dynamics in ferromagnetic manganites
• Identifying materials with charge-spin physics using charge-spin susceptibility computed from first principles
• Magnon self energy in the correlated ferromagnetic Kondo lattice model: spin-charge coupling effects on magnon excitations in manganites
• Multi-orbital quantum antiferromagnetism in iron pnictides --- effective spin couplings and quantum corrections to sublattice magnetization
• Role of atomic vacancies and second-neighbor antiferromagnetic-exchange coupling in a ferromagnetic nanoparticle