低维结构中Rashba电子的波导理论与自旋器件设计

Spin polarized transport's realization and control is an important subject in semiconductor spintronics, also one of main obstacles which impact realization of corresponding spin devices. In a variety of quantum structure in the two-dimensional electron gas (2DEGs), to control the spin polarized transport by utilizing Rashba spin-orbit interaction (RSOI) has been exclusively studied in recent years. Quantum waveguide theory is one of main tools to research electron transport in quantum waveguides. Based on this theory, we will study RSOI’s influence on spin transport in two-dimensional waveguide structure and one-dimensional ring system in this project. Via comparing the analytical expressions and numerical results of different waveguide geometry structure and different initial spin states, we can analyze various factors’ influence on spin transport and explore how to design ideal spintronics devices. In addition, we plan to consider spin flip and polarization in structure with various rings in this project, and sum up mathematical and physical mechanisms of these phenomenons.

自旋极化输运的实现与控制是半导体自旋电子学中的重要课题，也是相应的自旋器件能否实现的主要障碍之一。在二维电子气中构造各种量子结构，通过Rasbha自旋轨道耦合来操控自旋是近些年理论研究方向的热点。量子波导理论是研究低维纳米量子结构中电子输运的主要理论工具之一，本项目以此理论为出发点，考察在二维波导结构以及一维环型体系中，Rashba 自旋轨道耦合及器件形状等因素对电子自旋输运的影响。通过对比不同的波导几何结构以及不同的自旋初态所得到的解析表达式和数值计算结果，分析各因素对于自旋输运的影响，探索如何设计理想中的自旋器件。此外，本项目还将考虑具有各类环型结构的体系中自旋的翻转和极化等现象，总结这类效应产生的数学和物理机制。

围绕着低维结构中Rashba电子的自旋输运的控制，从自旋极化的产生和自旋翻转的实现等两个方面展开系统的研究，取得了一系列有特色的创新性成果。特别是对于二维电子气中的一维介观环中的输运有了全面的结论，对于半导体自旋器件的制作有极大的理论指导意义。