利用規範轉換計算二維自旋軌道耦合系統中的電子自旋進動

Calculation of Spin Precession by Gauge Transformation in 2D Spin-Orbit Coupling System

黃振崗(Chen-Kang Huang)

指導教授 ： 張慶瑞

國立臺灣大學/理學院/物理研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.00799

摘要

自旋軌道耦合作用(Spin-Orbit Coupling)被廣泛的應用在各類自旋電子學原件中，因為透過這個效應可以不使用磁場就控制電子自旋。我們將討論在金屬和半導體混成材質上兩種主要的自旋軌道耦合作用，分別是Rashba和Dresselhaus效應，並且將兩種效應合在一起用一個規範場(Non-Abelian Gauge Field)來表示，利用這個場我們計算了二維平面上電子自旋在自旋軌道耦合效應作用下的各種傳輸表現。

關鍵字

自旋軌道耦合效應 ； 自旋電子學 ； 規範轉換

並列摘要

The spin-orbit(SO) interaction has widely applied in proposals of spintronic devices. It offers an approach to control the election spin without external magnetic field in semiconductor and metallic nanostructures. The dominant SO couplings which are relevant to planar semiconductor heterostructures are the Rashba and Dresselhaus effects. The former is due to the structure inversion asymmetry(SIA) which can be controlled by gate voltage and the latter is due to the bulk inversion asymmetry(BIA). In this thesis, we study geometrical effects of SO interaction on two-dimensional electrongas(2DEG) system. It is showed the SO coupling including Rashba and Dresselhaus terms can be regarded as a non-Abelian SU(2) gauge field. In chapter two, we survey on some well-known theories in two field of physics; they are spin-orbit coupling thoery and gauge transformation. In
chapter three we will use some tricks to maneuvre the gauge transformation in calculation spin precession in spin-orbit field. Extending this method, we can use SO gauge field to calculate the spin transport in a two-dimensional system which is affected by space-dependent SO couplings. In chapter four, we make the summary and give some directions of future work.

並列關鍵字

spin-orbit coupling ； spintronics ； gauge transformation

參考文獻

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