臺灣博碩士論文加值系統

我們討論了磁性雜質的大小跟磁矩的方向對多層結構中穿透係數的影響。其中介紹了transfer-matrtix的方法，並且針對我們處理的結構所需引入了自旋座標轉換和機率流衰減因子來修改原始的transfer-matrix公式。

We discuss the e¤ects of the size, magnitude and orientation of magnetic
moment of magnetic impurities. To discuss the transport in quantum well
aspect, the systematic method which named transfer-matrix formalism is
needed for solving the transmission and refection probability.

1 Motivation 9
2 theoretical calculation 11
2.1 Hamiltonian . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.1.1 ferromaget region . . . . . . . . . . . . . . . . . . . . . 12
2.2 wave functions and eigenenergies . . . . . . . . . . . . . . . . 13
2.3 The transfer-matrix formalism . . . . . . . . . . . . . . . . . . 15
2.3.1 Single F/M case . . . . . . . . . . . . . . . . . . . . . . 15
2.3.2 Generalized into N layers case . . . . . . . . . . . . . . 18
2.4 The modi…cation of the transfer-matrix formalism . . . . . . . 20
2.4.1 The spinor transformation?? . . . . . . . . . . . . . . . 20
2.4.2 The defusive case . . . . . . . . . . . . . . . . . . . . . 22
2.5 The Landuer formula . . . . . . . . . . . . . . . . . . . . . . . 25
3 Numerical Results and Discussions 27
3.1 Analyze the properties of transmission probability . . . . . . . 27
3.1.1 T vs L . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.1.2 Transmission probability versus particle energy . . . . 36
4 Conclusion 45
A The derivation of some formula 47
A.1 Solve the eigenvalue problems for the ferromagnetic region . . 47

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