Theory of Quantum Transport based on Spin and Orbital.

一个电子具有自由、旋转、电荷、轨道的内部程度，将上升到材料属性。电子的电荷流动是当前的，电子是基于对当前的控制。基于自旋电流的电子学被称为自旋电子学。轨道的动力学也可能被预期在过渡金属氧化物中。在这个项目中，量子传输理论开始与这些内部级的动力学组成，由一个实验组组成。1.这表明自旋电流和电荷电流之间的转换可以在一个非本地自旋霍尔设备上获得。既然转换是Onsager递归关系中的一个，它是物理学中一个非常基本的概念。2.在一个超导体/铁磁/超导体隧道联合的设备上，Josephson当前在两个超导体之间流动有额外的相位， π。这就是所谓的π交叉点。我们建议使用π-结的超导电环，可能会使用为没有应用的磁性字段的量子计算设备（量子位）。在许多过渡金属氧化物中，如Na_xCoO_2，我们认为轨道的发育导致一个电子晶格与晶体管不同。作为一个结果，一种新颖的物理特性是预期的。基于理论，我们在Na_xCoO_2中形成了异常的霍尔效应和巨大的热功率观测结果。在这个项目中，我们研究了各种量子传输现象，从一个电子的内部程度开始。

An electron has the internal degrees of freedom, spin・charge・orbital, which give rise to materials properties. The flow of charge of electrons is current, and electronics is based on the control of current. The electronics based on spin current is called spin-electronics. The dynamics of orbital is also expected in transition metal oxides.In this project, the theory of quantum transport starting with the dynamics of these internal degrees of freedom of an electron has been constructed.1.It is shown that the conversion between spin current and charge current can be obtained in a non-local spin Hall device together with an experimental group. Since the conversion is one of the Onsager reciprocal relations, it is a very basic concept in physics.2.In a device consisting of superconductor/ferromagnet/superconductor tunnel junctions, the Josephson current flowing between two superconductors has the extra phase, π. This is called the π-junction. We have proposed that a superconducting ring with π-junction may be used as a quantum computing device (qubit) without applied magnetic field.3.In several transition metal oxides such as Na_xCoO_2,we have shown that the orbital degeneracy causes an electronic lattice with is different from the crystal one. As a result, a variety of novel physical properties are expected. Based on the theory, we have formulated the anomalous Hall effect and giant thermopower observed in Na_xCoO_2.In this project, we have investigated various quantum transport phenomena starting with the internal degrees of freedom of an electron.