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

相关量子线中的自旋轨道耦合：新相和自旋输运

• 批准号: 157897820
• 负责人: Professorin Dr. Sabine Andergassen
• 金额: --
• 依托单位: Institut für Festkörperphysik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2011-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/157897820?language=en
• 关键词: Spin; orbit; coupling; correlated; quantum

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.

准一维量子线是未来自旋信息处理器件（自旋电子学）的基石。特别地，提出了几种基于量子线的设置，其在存在Rashba自旋轨道耦合的情况下操作的自旋过滤器。为了获得对自旋的最佳控制，只应该占据金属丝的第一个子带（严格的一维系统）。在大多数的理论研究中，所涉及的电子之间的库仑排斥被忽略。对于没有自旋轨道耦合的严格一维系统，两粒子（库仑）相互作用对低能物理有着显著的影响。它可以导致在自旋和/或电荷激发光谱中具有间隙的相位。但是，即使在仍然是金属的系统（Luttinger液体）中，低能光谱和输运性质也会发生强烈的改变，特别是在存在非均匀性的情况下，例如与高维铅的接触。为了详细了解未来基于量子线的自旋电子器件的性能，因此必须对这种系统中的自旋轨道相互作用和电子相关性的相互作用进行彻底的理论理解。我们将集中在两个特定的方面：a）可能的新的阶段，从这种相互作用和B）特征自旋输运性质的非均匀线。