Intrinsic localized spin-wave modes in antiferromagnetic chains with single-ion easy-axis anisotropy

Abstract

The dynamical properties of intrinsic localized spin-wave modes (ILSM's) in perfect antiferromagnetic chains of classical spins with on-site easy-axis anisotropy are investigated. Only ILSM's of odd parity exist below the plane-wave magnon frequency band. The degree of localization increases as either the maximum spin deviation or the ratio of the anisotropy constant to the exchange coupling constant, $\frac{D}{J}$, increases. Traveling ILSM's can also be excited; however, they become pinned for large $\frac{D}{J}$.