光學拓樸準粒子skyrmion和meron描述光與物質交互作用系統下所產生的自旋紋理的拓樸保護特性，在磁性材料儲存、自旋電子學元件與光學資訊傳遞應用中扮演重要角色。傳統上，可以用奈米金屬slit結構激發表面電漿子Surface plasmon polaritons(SPPs)，以此產生Neel-type skyrmion或meron。由於SPPs場的行進特性，無法得到其他型態的拓樸準粒子，我設計新的結構引入Localized surface plasmon(LSP)於結構邊角散射場的影響，讓拓樸準粒子的自旋紋理具有非零的helicity。此外，我們探討表面電漿波的自旋紋理在不同高度下逐漸演化，隨著高度增加，場的機制會從原本SPP主導逐漸轉向LSP主導，最終成功產生出複合型態的拓樸準粒子，例如twisted-type, Bloch-type, anti-type meron lattice。

In light-matter interaction system, optical topological quasi-particles, skyrmion and meron describe the topologically protected spin texture property which has important roles in application of magnetic material storage, spintronics device and optics information transmission. Traditionally, we can excite surface plasmon polaritons(SPPs) through nano-metallic slit structure to produce Neel-type skyrmion or meron. Due to transverse character of SPPs field, we cannot get other type topological quasi-particles. We design a new structure to introduce the scattered field of localized surface plasmon(LSP) which is confined at edges so that spin texture of quasi-particle can has non-zero helicity. On the other hand, we investigate on plasmonic spin texture evolution at different heights. Through increasing height, fields is originally dominated by SPP gradually turn into by LSP and we successfully create multi-types topological quasi-particle at the end, such as twisted-type, Bloch-type, anti-type meron lattice.

第一章 序論
1-1 Topology theory and topological quasi-particle--------------2
1-2 Winding number----------------------------------------------3
1-3 Skyrmion and skyrmion zoology-------------------------------6
1-4 Meron-------------------------------------------------------8
1-5 Surface plasma----------------------------------------------9
第二章 實驗與模擬
2-1 Electric Neel-type skyrmion
2-1-1 Experiment-------------------------------------------------14
2-1-2 Simulation-------------------------------------------------16
2-2 Spin skyrmion
2-2-1 FDTD simulation--------------------------------------------17
2-2-2 Structure design－Bloch-type, twisted-type-----------------19
2-2-3 Influence of LSP-------------------------------------------22
2-3 Meron
2-3-1 Experiment meron lattice-----------------------------------23
2-3-2 FDTD simulation and analytical solution--------------------24
2-3-3 Structure design－Single twisted-type meron----------------28
第三章 凹結構
3-1 Concave device design--------------------------------------29
3-2 X-Y plane at different heights-----------------------------31
第四章 電漿波自旋紋理演化
4-1 X-Z cross section plane------------------------------------32
4-1-1 Spin and field pattern-------------------------------------32
4-2 X-Y plane at different heights-----------------------------35
4-2-1 Spin and field pattern-------------------------------------35
4-2-2 Winding number calculation---------------------------------41
4-2-3 Swirl of spin----------------------------------------------44
第五章 結論與展望
5-1 Conclusion-------------------------------------------------45
5-2 Future work and prospects----------------------------------47
參考文獻------------------------------------------------------------48

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