Theoretical study of multi-terminal quantum dot: proposal of tunable spin Hall effect

对半导体多端子量子点的物理现象进行了理论研究。(1)利用具有自旋-轨道相互作用的多端量子点，我们发现了自旋霍尔效应产生的自旋极化电流。自旋-极化比可以通过栅极电压进行电调。(2)研究了嵌入小环的量子点中的近藤效应。我们已经阐明了近藤效应与环大小的关系，输运性质中的非弹性过程，以及在多端几何结构中检测到的电子相的信息。(3)考虑了自旋-轨道相互作用，解释了InAs量子点的各向异性g因子和InSb纳米线中观察到的反常约瑟夫森效应。

Physical phenomena have been theoretically investigated in multi-terminal quantum dots fabricated on semiconductors. (1) We have found the generation of spin-polarized current due to the spin Hall effect, using a multi-terminal quantum dot with spin-orbit interaction. The spin-polarization ratio is electrically tunable via gate voltages. (2) The Kondo effect has been studied in a quantum dot embedded in a small ring. We have elucidated the ring-size dependence of the Kondo effect, inelastic processes in transport properties, and information on the electron phase detected in the multi-terminal geometry. (3) The anisotropic g-factors in InAs quantum dot and anomalous Josephson effect observed in InSb nanowires have been explained, taking into account the spin-orbit interaction.