Spin-wave dispersion and exchange stiffness in Nd${}_2$Fe${}_{14}$B and $R$Fe${}_{11}$Ti ($R$=Y, Nd, Sm) from first-principles calculations

Abstract

We theoretically investigate spin-wave dispersion in rare-earth magnet compounds by using first-principles calculations and a method we call the reciprocal-space algorithm (RSA). The value of the calculated exchange stiffness for Nd${}_2$Fe${}_{14}$B is within the range of reported experimental values. We find that the exchange stiffness is considerably anisotropic when only short-range exchange couplings are considered, whereas inclusion of long-range couplings weakens the anisotropy. In contrast, $R$Fe${}_{11}$Ti ($R$=Y, Nd, Sm) shows large anisotropy in the exchange stiffness.

arXiv comment8 pages, 6 figures

References in corpus (8)

• Ab-initio calculations of exchange interactions, spin-wave stiffness constants, and Curie temperatures of Fe, Co, and Ni
• An ab initio effective Hamiltonian for magnetism including longitudinal spin fluctuations
• Calculating temperature-dependent properties of Nd${}_2$Fe${}_{14}$B permanent magnets by atomistic spin model simulations
• Anisotropy of exchange stiffness based on atomic-scale magnetic properties in rare-earth permanent magnet Nd${}_2$Fe${}_{14}$B
• Spin wave dispersion of 3d ferromagnets based on QSGW calculations
• Role of typical elements in Nd${}_2$Fe${}_{14}$$X$ ($X$ = B, C, N, O, F)
• First-principles study of spin-wave dispersion in Sm(Fe${}_{1-x}$Co${}_x$)${}_{12}$
• Spin wave stiffness and exchange stiffness of doped permalloy via ab-initio calculation

Cited by in corpus (1)

• Non-linear extension of the dynamical linear response of spins; extended Heisenberg model