Optically induced non-equilibrium spin transport in mesoscopic semiconductor circuits

介观半导体电路中的光致非平衡自旋输运

• 批准号: 40915753
• 负责人: Professor Dr. Alexander Walter Holleitner
• 金额: --
• 依托单位: Walter Schottky Institut für physikalische Grundlagen der Halbleiterelektronik (WSI)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/40915753?language=en
• 关键词: Optically; induced; non; equilibrium; spin

Mesoscopic semiconductor circuits shall be systematically characterized and explored to enable an efficient information processing based upon the electronic spin degree of freedom in such circuits. To this end, a spatially resolved, spin-polarized photocurrent mapping technique shall be applied to mesoscopic circuits defined in two-dimensional electron reservoirs of GaAs-based heterostructures. The spin-polarized photocurrents will be locally analyzed by an optoelectronic spin detector exploiting spin-split one-dimensional subbands of a quantum point contact (QPC). Hereby, mesoscopic spin-transport phenomena of a non-equilibrium spin population shall be explored in the ballistic and diffusive regime. Particular emphasize will be placed on spin scattering processes at the transition from a two-dimensional to a one-dimensional spin system. We furthermore expect insights into spin relaxation mechanisms induced by spin-orbit coupling terms, i.e. due to structural and bulk inversion asymmetry. The proposed experiments shall prepare ground for mesoscopic optoelectronic spin devices. Within the SPP, we further plan to transfer our confocal optoelectronic characterization scheme towards InAs-based and ZnO-based circuits in order to explore the spin-polarized photocurrent properties in these materials as well.

应系统地表征和探索介观半导体电路，以基于此类电路中的电子自旋自由度实现高效的信息处理。为此，一个空间分辨，自旋极化光电流映射技术应适用于介观电路中定义的GaAs基异质结构的二维电子水库。利用量子点接触（QPC）的自旋分裂一维子带，利用光电自旋探测器对自旋极化光电流进行局部分析。因此，介观自旋输运现象的非平衡自旋人口将探讨在弹道和扩散制度。特别强调将放在从二维到一维自旋系统的过渡自旋散射过程。此外，我们还期望深入了解自旋-轨道耦合项引起的自旋弛豫机制，即由于结构和体反转不对称性。所提出的实验将为介观光电自旋器件奠定基础。在SPP中，我们进一步计划将我们的共焦光电表征方案转移到InAs基和ZnO基电路中，以探索这些材料中的自旋极化光电流特性。