Spin-orbit coupling in correlated quantum wires: novel phases and spin-transport

讨论了准一维量子线äs信息处理（自旋电子学）的未来自旋器件的构建模块。特别地，提出了几种基于量子线的装置äs自旋滤波器在Rashba自旋轨道耦合存在下工作。为了获得对自旋的最佳控制，应该只占用导线的第一个子带（严格的一维系统）。在大多数理论研究中，所涉及的电子之间的库仑排斥是被忽略的。对于没有自旋轨道耦合的严格一维系统，已知两粒子（库仑）相互作用对低能物理有显著影响。它可以导致自旋和/或电荷激发光谱中有间隙的相。但即使在保持金属（Luttinger液体）的系统中，低能谱和输运性质也会发生强烈变化，特别是在不均匀性存在的情况下，例如äs与高维引线的接触。为了详细了解未来基于量子线的自旋电子器件的性能，因此必须从理论上全面了解自旋轨道相互作用和电子相关在这种系统中的相互作用。我们将重点关注两个方面：a)由这种相互作用产生的可能的新相和b)非均匀导线中的特征自旋输运特性。

Quasi one-dimensional quantum wires are discussed äs building blocks of future spin-based devices for information processing (spintronics). In particular, several quantum wire based Setups were proposed äs spin-filters operating in presence of Rashba spin-orbit coupling. To gain optimal control over the spin only the first subband of the wire should be occupied (strictly one-dimensional System). In most of the theoretical studies the Coulomb repulsion between the involved electrons is neglected. For strictly one-dimensional Systems without spin-orbit coupling the twoparticle (Coulomb) interaction is known to have a dramatic effect on the low-energy physics. It can lead to phases with gaps in the spin and/or Charge excitation spectrum. But even in Systems which remain metallic (Luttinger liquids) the low-energy spectral and transport properties are strongly altered, in particular in the presence of inhomogeneities such äs contacts to higher-dimensional leads. For a detailed understanding of the performance of future quantum wire based spintronic devices it is thus mandatory to gain a thorough theoretical understanding of the interplay of spinorbit interaction and electron correlations in such Systems. We will focus on two particular aspects: a) possible novel phases resulting from this interplay and b) characteristic spin-transport properties in inhomogeneous wires.