從二維空間到準一維空間之自旋電子傳輸

本篇論文將探討自旋電子在自旋軌道偶和的傳輸從二維系統到準一維系統。利用非平衡格林函數在緊核模型和碎形理論，模擬自旋電子和電子在不同形狀的元件分布情形，是否有碎形的情況產生。同時隨著形狀的改變，可以傳導的面積隨之減少，因而傳輸的能力也會有所不同。接著比較相通數量接點的線型傳輸元件，藉以分析出碎形所造成的效應。

關鍵字

電子傳輸；碎形；量子點；格林函數

並列摘要

This thesis is theoretical study of spatial behavior of spin from two dimensions to quasi-one dimension subject to the Rashba spin-orbital coupling. The theoretical method is Non-Equilibrium Green’s Function (NEGF) in tightbinding model and lead self-energy model. The result of NEGF in 2D simple tight-binding square-lattice Hamiltonian and two normal metal leads is studied. The Spin Hall effect presents in the distribution of spin density. We tune the two-dimensional square-lattice into quasi-one dimensional fractal shape by taking off the element of matrix of Hamiltonian. In the different shape we produced, the local spin density and transmission are discussed and compared with linear shape in each cases.

並列關鍵字

Quantum Dot ； Spin ； Transport ； Fractal Structure ； LKF ； Landauer Keldysh Formalism ； NEGF ； Non-Equilibrium Green’s Function

參考文獻

[3] S.-H. Chen, M.-H. Liu, K.-W. Chen, and C.-R. Chang. Spin accumulation oscillation

105(7):07E908, 2009.

[2] S.-H. Chen, I. Klik, and C.-R. Chang. Spin hall effect in a square 2deg sample with

a central defect. Journal of Magnetism and Magnetic Materials, 322(9-12):1452–

and current vortex in the landauer setup with locally applied biases. Journal of

國際替代計量

從二維空間到準一維空間之自旋電子傳輸

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