利用自旋偏極化穿隧電子掃瞄顯微鏡與能譜解析鈷奈 米島嶼在銅(111)上的磁性量子限制與相互作用

Abstract

三角鈷奈米島嶼在銅(111)上的堆積行為與垂直平面的磁化方向在此篇論文中被研究，由於量子限制，利用電子穿隧掃描顯微鏡可以解析在這個系統下的電子干涉模型與表面電子能態偏移，我們可以利用自由電子的駐波態去模擬實驗下的電子干涉模型，並驗證利用非自旋偏極化的穿隧電子掃瞄顯微鏡亦可解析出磁性的駐波模型。此外，我們發現到某些相連的鈷島嶼的自旋呈現反向平行，從我們的統計與計算，我們認為磁偶極矩足夠與鐵磁性藕和競爭並保持鈷奈米島嶼呈現自旋反向平行的情況。

The stacking behaviors and out of plane magnetization of bilayer triangular Co nanoislands on Cu(111) were studied. Due to quantum confinement, the interference patterns and surface state shift can be resolved in this system by scanning tunneling microscopy and spectroscopy. We used the free electron model to fit the interference patterns with experimental data, and we discovered that the magnetic standing wave patterns can also be resolved by non spin-polarized STM. Furthermore, we observed some conjoint Co islands with anti-parallel spin alignment. From our statistical result and calculation, we deduced that dipolar interaction is strong enough to compete with ferromagnetic coupling to preserve the anti-parallel spin alignment in two conjoint Co nanoislands.