Spin states in carbon nanotube and graphene double quantum dots with charge detection

带电荷检测的碳纳米管和石墨烯双量子点中的自旋态

• 批准号: 64100339
• 负责人: Dr. Carola Meyer
• 金额: --
• 依托单位: Fach Physik
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/64100339?language=en
• 关键词: Spin; states; carbon; nanotube; graphene

Carbon nanostructures based on graphene and carbon nanotubes (CNTs) are intrinsically low-dimensional systems with promising properties for quantum electronics. Spin scattering in both material systems is expected to be small because of their low spin-orbit coupling and the small abundance of nuclear spins. Therefore, long spin relaxation and coherence times are expected, which are essential for coherent spin-based information processing. In this project, we want to explore the fundamental properties of carbon nanostructures and the electron spin relaxation within these systems. This is an important step for the development of solid-state spin qubits and quantum electronic devices in general. The spin states will be studied in quantum dots fabricated in carbon nanotubes (part A, FZJ) and in graphene in the few-electron / few-hole regime (part B, RWTH). The states will be characterized by low-loise quantum transport measurements at varying magnetic field. Different challenges have to be addressed for both material systems. In the CNT sub-project, the focus will be on implementing high-frequency techniques for the quantitative assessment of spin relaxation times and Rabi oscillations. In the graphene sub-project we focus on the fabrication and characterization of graphene double quantum dots with integrated charge detection. The elements realized in the two parts will allow measurements of spin coherence times in both material systems.

基于石墨烯和碳纳米管（CNTs）的碳纳米结构本质上是低维体系，具有良好的量子电子学性能。两种材料系统中的自旋散射预计是小的，因为它们的低自旋-轨道耦合和小丰度的核自旋。因此，长的自旋弛豫和相干时间是预期的，这是必要的相干自旋为基础的信息处理。在这个项目中，我们希望探索碳纳米结构的基本特性以及这些系统中的电子自旋弛豫。这是固态自旋量子比特和量子电子器件发展的重要一步。自旋态将在碳纳米管（部分A，FZJ）和石墨烯中的少电子/少空穴制度（部分B，RWTH）制造的量子点中进行研究。这些态的特征将通过在变化磁场下的低洛伊丝量子输运测量来表征。两种材料系统必须应对不同的挑战。在CNT分项目中，重点将是实施定量评估自旋弛豫时间和拉比振荡的高频技术。在石墨烯子项目中，我们专注于集成电荷检测的石墨烯双量子点的制备和表征。在这两个部分中实现的元件将允许在两种材料系统中测量自旋相干时间。