有限铁磁—反铁磁线链中的自旋波谱及其激发

本文研究了由交换作用耦合起来的有限长铁磁和反铁磁链组成的自旋系统。计算了系统的自旋波的波谱及其在微波场中的激发强度。在所得结果的基础上,讨论了具有反铁磁氧化层的铁磁薄膜的自旋波共振。阐明了等效地使用唯象普遍边界条件的可能性。根据理论,对等效的表面各向异性能作了估计,得到的数值与实验值很好地符合。

THE SPIN-WAVE SPECTRUM AND ITS EXCITATION IN A FINITE FERROMAGNETIC-ANTIFERROMAGNETIC LINEAR CHAIN

The system of spins in a finite ferromagnetic-antiferromagnetic chain, coupled by exchange interaction, is investigated. The spin-wave spectrum and the intensities of its excitation are calculated. On the basis of the results obtained, the spin-wave resonance of a ferromagnetic film with a surface of antiferromagnetic oxide is discussed. The validity of the general phenomenological boundary condition is elucidated. The value estimated for the equivalent surface anisotropy energy according to our theory is found to be in fairly good agreement with experimental data.