Tailoring noncollinear magnetism by misfit dislocation lines

Data for the publication: "The large epitaxial stress induced by the misfit between a triple atomic layer Fe film and an Ir(111) substrate is relieved by the formation of a dense dislocation line network. Spin-polarized scanning tunneling microscopy investigations show that the strain is locally varying within the Fe film and that this variation affects the magnetic state of the system. Two types of dislocation line regions can be distinguished and both exhibit spin spirals with strain-dependent periods (ranging from 3 to 10 nm). Using a simple micromagnetic model, we attribute the changes of the period of the spin spirals to variations of the effective exchange coupling in the magnetic film. This assumption is supported by the observed dependence of the saturation magnetic field on the period of the zero-field spin spiral. Moreover, magnetic skyrmions appear in an external magnetic field only in one type of dislocation line area, which we impute to the different pinning properties of the dislocation lines."

本论文配套发表数据：三层原子层铁（Fe）薄膜与铱（Ir）(111)衬底之间的失配引发的强外延应力，可通过形成致密位错线网络得以缓解。自旋极化扫描隧道显微镜（spin-polarized scanning tunneling microscopy）研究显示，Fe薄膜内部存在局域应变变化，且该应变变化会影响体系的磁状态。可区分出两类位错线区域，两类区域均呈现出与应变相关的自旋螺旋结构，其周期范围为3至10 nm。通过简单的微磁学模型，我们将自旋螺旋周期的变化归因于磁性薄膜中有效交换耦合的改变。这一假设得到了观测到的饱和磁场与零场自旋螺旋周期之间的依赖关系的支持。此外，磁性斯格明子仅在一类位错线区域的外磁场条件下出现，我们将此现象归因于不同位错线具有不同的钉扎特性。