在一维均匀铁磁链中磁振动的内禀局域模(英文)

Intrinsic localized modes of magnetic vibrations in a homogeneous one-dimensional ferromagnetic chain

利用多标度方法和准离散近似,我们考察了在一维均匀铁磁链中磁振动的内禀局域模;结果表明磁振动的内禀局域模在许多方面都与晶格振动的内禀局域模相类似;它们是近邻自旋之间非线性相互作用的结果。这种内禀局域模的存在并没有破坏系统的平移对称性,它们能在任何晶格位被激发。它们的量子本征频率在简谐磁振动频带的上方。

By use of the method of multiple scales and a quasidiscreteness approximation, we investigate the intrinsic localized modes of magnetic vibrations in a homogeneous one-dimensional ferromagnetic chain. It is shown that its localization properties are similar to those of the intrinsic localized modes of atomic vibrations. The existence of the intrinsic localized modes does not destroy the translational symmetry of the system. Their existence is a result of nonlinear interaction between neighboring spins, they can be excited at any lattice site. The quantum eigenfrequencies of these localized modes are above the frequency band of the harmonic magnetic vibrations.